Free Labs

Free Virtual Learning Labs

Guided lab experiments with step-by-step workflows, animated simulations, and real data collection. All free, all in your browser.

For Ages 5 to 7

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Showing 394 labs

Chemistry

Dissolving Rate Lab

Compare temperature, stirring, and particle size in a repeatable dissolving model. Track dissolved mass and separate dissolving rate from solubility.

Evaporation Rate Lab

Compare temperature, exposed surface area, airflow, and humidity in a repeatable evaporation model. Record water mass over time and explain controlled trials.

Gas Laws Lab

Explore Boyle's, Charles's, and Gay-Lussac's gas laws with animated particles. Adjust pressure, volume, temperature, and moles to discover relationships experimentally

Gas Collection over Water & Partial Pressure Lab

Collect a gas over water in a eudiometer and apply Dalton's law to subtract the water vapor pressure, finding the dry gas partial pressure and the moles of gas via the ideal gas law

Chemical Kinetics Lab

Simulate reaction rates with the Arrhenius equation. Adjust concentration, temperature, and catalysts to observe how particle collision frequency and rate constants change

Reaction Mechanism Energy Profile Lab

Build a one-step or two-step reaction mechanism, set the activation energy and enthalpy change, and add a catalyst. Read the potential-energy profile with its transition states and intermediate, identify the rate-determining step, compare forward and reverse activation energies, and measure how much a catalyst speeds the reaction up.

Diffusion & Osmosis Lab

Watch particles move across a semipermeable membrane. Adjust concentrations on each side and observe diffusion, osmosis, and equilibrium with Fick's law calculations

Titration Lab

Simulate acid-base titration with a virtual burette. Watch pH curves develop in real time, find equivalence points, and compare strong and weak acid behavior with indicator color changes

Calorimetry Lab

Mix substances at different temperatures and observe heat exchange over time. Calculate specific heat, compare coffee cup and bomb calorimeters, and model heat loss

Serial Dilution & Standard Curve Lab

Perform multi-step serial dilutions, measure absorbance with Beer-Lambert law, build a standard curve with linear regression, and determine unknown concentrations

Calorimetry Virtual Experiment Lab

Run a full calorimetry investigation. Three modes derive an unknown specific heat from a slope, calibrate the calorimeter heat capacity C_cal from water mixes, and measure the molar heat of combustion of a fuel sample. Replicated trials, regression, residuals, propagated uncertainty, and percent-error analysis

Reaction Rate Investigation Lab

Determine the order of a chemical reaction by integrated rate law linearization, derive rate constants by the initial-rates method, and find activation energy from the Arrhenius plot. Replicated trials with regression, residuals, and percent-error analysis

Equilibrium Shift Investigation Lab

Le Chatelier investigation with quantitative Kc tracking. Apply concentration spikes, sweep temperature on a vant Hoff plot, and change volume on five gas-phase equilibria. Predict shift direction, then verify with Q vs K.

Solubility Curve Investigation Lab

Build solubility curves for seven preset solutes by sweeping temperature 0 to 100 C. Fit a line, classify dissolution endothermic vs exothermic, compare two solutes on the same axes, and predict the mass that crystallizes when a saturated solution is cooled.

Flame Test & Cation Identification Lab

Heat metal salts in a simulated Bunsen flame to observe characteristic flame colors and identify metal cations, with an unknown-identification challenge, data table, and lab report.

Qualitative Analysis: Unknown Ion Identification Lab

Identify an unknown metal cation by adding reagents and observing precipitate colors, narrowing the possibilities with a systematic scheme of tests and a data table.

Atomic Emission Lab

Select elements and observe their emission line spectra. Explore the Rydberg equation, Bohr model energy levels, and flame test colors for hydrogen and other elements

Chromatography Lab

Simulate paper chromatography with animated solvent front and spot separation. Calculate Rf values, compare polarities, and identify unknown compounds by matching standards

Electrochemistry Lab

Build galvanic and electrolytic cells by selecting anode and cathode metals. Calculate cell potential with the Nernst equation and explore Gibbs free energy relationships

Electrolysis & Metal Plating Lab

Set the current, plating time, metal, and electrode area, then predict how much metal deposits on the cathode using Faraday's law of electrolysis. See the charge passed, moles of electrons, mass plated, and plating thickness, and compare why silver plates more grams per coulomb than copper or gold.

Stoichiometry Lab

Identify limiting reagents, calculate theoretical and percent yield, and trace dimensional analysis step by step with visual mole bar charts

Gravimetric Analysis Lab

Determine the percent composition of a sample by precipitating, filtering, drying, and weighing the precipitate, using the gravimetric factor with a step-by-step procedure, data table, and lab report.

Fractional Distillation Lab

Separate a liquid mixture by boiling point in a fractionating column, scrubbing through the distillation to watch the head temperature plateau at each component's boiling point and read the distillation curve.

Equilibrium Lab

Explore chemical equilibrium with Le Chatelier's principle. Adjust concentrations and temperature to watch Q approach Keq with animated particle shifts and ICE tables

Reaction Types Lab

Classify reactions as synthesis, decomposition, single replacement, double replacement, or combustion. Watch animated molecular rearrangements and verify atom conservation

Thermochemistry Lab

Build enthalpy diagrams, apply Hess's law across multiple reaction paths, and calculate enthalpy changes from bond energies with interactive energy level visualizations

Buffer & Acid-Base Equilibrium Lab

Explore buffer chemistry with the Henderson-Hasselbalch equation. Select buffer systems, adjust acid and base concentrations, add strong acid or base, and compare buffered versus unbuffered pH response

Phase Changes & Phase Diagram Lab

Explore phase transitions with interactive heating curves and P-T phase diagrams. Watch temperature plateaus during melting and boiling, identify triple and critical points, and investigate colligative effects

Solubility & Ksp Lab

Explore solubility equilibrium with sparingly soluble salts. Calculate molar solubility from Ksp, observe the common ion effect, and predict precipitation by comparing ion product Q to Ksp

Electrolytes & Conductivity Lab

Test how strong, weak, and non-electrolyte solutions conduct electricity with a light-bulb conductivity apparatus, watching the bulb brightness and the ions in solution change with substance and concentration

Physical vs Chemical Change Lab

Classify twelve everyday scenarios as physical or chemical changes. Each scenario shows a visual cue, and a data table records your reasoning. A summary reveals your accuracy and explains each change type.

Mixtures Lab

Sort six everyday mixtures into heterogeneous and homogeneous types and learn which separation method works best for each (filtration, evaporation, decantation, magnet, distillation, chromatography).

States of Matter Lab

Drag a temperature slider to watch particles change between solid, liquid, and gas. Compare water, ethanol, mercury, iron, and oxygen using their real melting and boiling points.

Chemical Reactions Lab

Explore six common chemical reactions covering all five families: synthesis, decomposition, single replacement, double replacement, and combustion. See the balanced equation, real-world example, and observable change for each.

Molecular Orbital Visualizer

Interactive 3D visualization of molecular orbitals from LCAO. Sigma and pi bonding/antibonding combinations of 1s, 2s, 2pz, 2px atomic orbitals. Adjustable bond length and effective nuclear charge

Limiting Reactant & Percent Yield Lab

Pick a balanced reaction, set the amount of each reactant, and find the limiting reactant, the excess left over, the theoretical yield, and the percent yield from your actual yield. Record trials and write a full lab report.

Beer's Law & Spectrophotometry Lab

Build a standard curve from known concentrations, fit the Beer-Lambert line, then read an unknown's concentration from its absorbance. Adjust molar absorptivity and path length, see percent transmittance, and watch the cuvette darken.

Biology

Bird Beak Adaptation Lab

Follow inherited beak traits across generations as food availability changes. Compare repeatable population trials and explain natural selection.

Photosynthesis Rate Investigation Lab

Full quantitative photosynthesis investigation. Three modes sweep light, CO2, or temperature while holding the other two fixed. Fit Michaelis-Menten to extract V_max and K_m from light or CO2 response, or read T_opt from the bell-shaped temperature curve.

Hardy-Weinberg & Natural Selection Lab

Simulate allele frequency changes across generations under selection, drift, mutation, and migration. Test Hardy-Weinberg equilibrium with chi-square analysis, including an AP-level goodness-of-fit analyzer that takes observed AA/Aa/aa counts and reports expected counts, χ² statistic, critical value at α=0.05, p-value, and a reject/fail-to-reject decision

Population Ecology & Demography Lab

Investigate population dynamics through exponential and logistic growth, Lotka-Volterra predator-prey cycles, and harvest sustainability analysis. Discover carrying capacity, inflection points, and maximum sustainable yield

Predator-Prey Population Lab

Simulate Lotka-Volterra population dynamics with adjustable growth and predation rates. Observe oscillating prey and predator populations over time. NGSS MS-LS2.

Enzyme Activity Lab

Investigate enzyme activity by measuring reaction rates under different substrate concentrations, temperatures, and pH levels. Fit data to the Michaelis-Menten model, determine Km and Vmax experimentally, and explore competitive inhibition effects

Photosynthesis Lab

Investigate photosynthesis rates under different light intensities, CO2 concentrations, and temperatures. Discover limiting factors, find light compensation and saturation points, and measure net O2 production experimentally

Cellular Respiration Lab

Measure CO2 production and O2 consumption under different conditions. Compare aerobic vs anaerobic respiration, test temperature effects on metabolic rate, and calculate respiratory quotient for different substrates

Mitosis & Meiosis Lab

Count cells in different mitotic phases to calculate mitotic index. Estimate phase durations from proportions, compare cell cycle timing, and test phase distribution with chi-square analysis

Biodiversity & Habitat Fragmentation Lab

Investigate species diversity and habitat fragmentation. Calculate Simpson and Shannon-Wiener diversity indices, explore island biogeography and species-area relationships, and test how fragmentation and corridors affect species richness

Signal Transduction Lab

Investigate how cells detect and amplify chemical signals. Measure receptor occupancy, cascade amplification, and dose-response curves. Collect data, estimate EC50, and explore the molecular logic of cell signaling

Molecular Evolution Lab

Compare hemoglobin DNA sequences across species. Measure percent identity, compute Jukes-Cantor distances, build phylogenetic trees, and study how mutations affect protein translation

Plant Water Transport Lab

Investigate how leaf area, stomatal density, temperature, humidity, and light affect transpiration. Collect data from a virtual potometer and explore the cohesion-tension mechanism of water transport

Gene Regulation Lab

Build truth tables for the lac operon under different inducer and glucose conditions. Measure dose-response curves for gene expression and estimate the dissociation constant from half-maximal induction

Bacterial Transformation Lab

Simulate heat shock bacterial transformation. Adjust DNA concentration, heat shock duration, and recovery time to optimize colony growth on selective plates and calculate transformation efficiency

Gel Electrophoresis Lab

Run virtual restriction digests and gel electrophoresis. Adjust voltage, gel concentration, and run time to separate DNA fragments. Build standard curves and estimate unknown fragment sizes

Fruit Fly Behavior Lab

Investigate Drosophila behavior in choice chambers. Track fly positions over time under light, humidity, and chemical stimuli. Analyze preference with chi-square goodness-of-fit tests

Energy Dynamics & Food Web Lab

Explore energy flow through food webs with interactive trophic diagrams. Remove species to observe trophic cascades, track energy budgets, and verify the 10% transfer rule experimentally

Artificial Selection Lab

Simulate selective breeding over generations. Set a trait threshold, breed selected individuals, and verify the breeder's equation R = h²S with comparison mode for different heritabilities

Mendelian Genetics & Punnett Square Lab

Perform monohybrid, dihybrid, and sex-linked crosses with interactive Punnett squares. Explore complete, incomplete, and codominance patterns with genotypic and phenotypic ratios

DNA to Protein & Mutation Lab

Trace the central dogma from DNA to mRNA to protein. Explore reading frames, the codon table, and mutation types including silent, missense, nonsense, and frameshift

Plant Needs, Pollination & Seed Dispersal Lab

Grow virtual plants by varying sunlight and water, match flowers to pollinators, and identify how seeds travel to new locations

Life Cycles Lab

Sequence and compare the life cycles of butterfly, frog, plant, and bird - exploring metamorphosis and what makes each cycle unique

School Garden Ecosystem Mission

Build a garden ecosystem, predict how populations will change, then simulate predator-prey dynamics week by week. NGSS 5-LS2-1. Grades 3–5.

Inherited Traits & Variation Lab

Sort traits as inherited or learned, build a 3-generation family trait tree, and explore variation in a litter of puppies. NGSS 3-LS3. Grades 3–5.

Plant & Animal Structures Lab

Explore plant and animal structures, match each structure to its function, and solve habitat design challenges. NGSS 4-LS1-1. Grades 3–5.

Senses, Brain & Response Lab

Explore the five senses, trace stimulus-to-response pathways through the brain, and measure your own reaction time. NGSS 4-LS1-2. Grades 3–5.

Animal Groups & Survival Lab

Classify animals into vertebrate groups, explore survival adaptations across habitats, and simulate natural selection with a beetle population. NGSS 3-LS4. Grades 3–5.

Habitats & Adaptations Lab

Test animals in different habitats and score how well their adaptations help them survive. Discover why animals live where they do. Grades 3-5.

Needs of Living Things Lab

Compare what plants and animals need to survive. Record food, water, shelter, air, sunlight, and space for each living thing and find what they share. Grades K-1.

Parent & Baby Animals Lab

Record inherited traits for 8 parent-baby animal pairs. Investigate which babies look like their parents and which go through metamorphosis. Grades K-1.

Nature-Inspired Design Lab

Investigate biomimicry by matching human design problems to animal and plant parts that solve the same problem in nature. Record which parts work and which do not. Grades K-1.

Plant Growth Variables Lab

Control sunlight, water, soil type, and temperature to grow a virtual plant over 30 days. Change one variable at a time and record height to practice controlled experiments.

Circulatory System Flow Lab

Animated lab investigating how heart rate drives cardiac output and oxygen delivery. Adjust BPM, watch the animated heart pump blood through pulmonary and systemic circuits, record data at different activity levels, and write a lab report.

Respiratory System Breathing Lab

Animated breathing lab with SVG lungs and diaphragm that expand and contract in real time. Adjust breath rate and choose resting, light exercise, or exercise mode. Displays O2 consumed, CO2 produced, alveolar PO2/PCO2, and blood oxygen saturation. Data table tracks trials for hypothesis testing.

Nervous System Signal Speed Lab

Trigger an action potential and watch an animated signal propagate along a nerve to the brain. Myelination slider controls conduction velocity (0.5 to 120 m/s). Compare voluntary pathway vs reflex arc. Displays velocity, reaction time, refractory period, and max firing rate. Data table tracks fiber type vs response time.

Homeostasis Lab

Explore negative feedback loops for body temperature (32-43°C) and blood glucose (1-20 mmol/L). SVG feedback diagram highlights active steps. A speedometer-style gauge shows deviation from set point. Displays active corrective responses (sweating, shivering, insulin, glucagon), hormone levels, and severity labels from Normal to Severe Hypothermia or Diabetic Ketoacidosis.

Nephron Filtration & Osmoregulation Lab

Adjust blood pressure, ADH, salt intake, hydration, and plasma glucose, then trace filtrate through the five nephron segments. See how GFR autoregulation, tubular reabsorption, and ADH-driven water reabsorption set final urine volume, osmolarity, and sodium excretion, including the renal glucose threshold.

Muscle Contraction Sliding-Filament Lab

Adjust calcium concentration, ATP availability, and sarcomere length to see how a muscle fiber generates force through the sliding-filament mechanism. Watch actin and myosin overlap, count the active cross-bridges, explore the length-tension relationship, and see what happens to cross-bridge cycling without ATP.

Food Web Energy Pyramid Lab

Visualize energy flow through trophic levels using the 10% rule. Choose from 5 ecosystems (grassland, ocean, rainforest, freshwater, desert). SVG pyramid shows log-scale width proportional to energy at each level with heat-loss arrows. Adjust transfer efficiency (5-20%) and solar input. Data table tracks ecological efficiency across trials.

Photosynthesis Bubble Lab

Watch oxygen bubbles rise from pondweed as you change light intensity, lamp distance, water temperature, and CO2 level. Discover what speeds up and slows down photosynthesis in this classic middle-school experiment.

Cell Biology Lab

Toggle between animal and plant cell views. Click any organelle to read its function. Spot the three structures unique to plants (cell wall, chloroplast, central vacuole) and learn how the cell makes energy and proteins.

Epidemiology Spread Simulator

Simulate disease outbreaks using the SIR model and compare to real epidemic data (COVID-19, flu, Ebola, SARS, measles). Calibrate R0 and recovery rate to fit historical curves

Antibiotic Resistance Evolution Lab

Simulate a bacterial population of susceptible and resistant strains under antibiotic treatment. Set the dose, the dosing course, the starting resistant fraction, the mutation rate, and the fitness cost, then run it and watch natural selection drive resistance. See why an incomplete course or a low dose lets resistant survivors take over, and how a full course can clear the infection.

Mark-Recapture Population Estimator

Estimate an unknown wildlife population by tagging a first capture, releasing, then recapturing. Compare the Lincoln-Petersen and Chapman estimators and see how sample size sets the confidence interval.

Ecological Succession Simulator

Watch a barren landscape recover after lava, fire, or flood. Adjust climate and disturbance, then run the simulation to see pioneer species, shrubs, and forest replace one another and track diversity over time.

Animal Migration Route Builder

Plan a migration from breeding to wintering grounds. Pick a species and route, add food stops, and set weather and headwind, then see the energy budget, energy balance, and survival probability. Discover why the shortest route is not always the safest.

Earth Science

Air Pressure and Weather Instruments Lab

Compare atmospheric pressure at different altitudes with pressure inside a sealed container. Record barometer readings and explain pressure imbalances.

Water Quality & Eutrophication Lab

Collect water quality measurements from simulated sampling sites, calculate a Water Quality Index, and investigate how nutrient loading leads to algal blooms and dissolved oxygen crashes

Greenhouse Effect & Climate Lab

Investigate Earth's energy budget and greenhouse effect. Adjust CO2 levels and albedo, measure temperature response, explore feedback loops, and compare emission scenarios from pre-industrial to RCP 8.5

Air Pollution Lab

Investigate how temperature inversions and wind speed affect air quality. Vary inversion height, emission rates, and wind to measure AQI, pollutant concentration, and mixing volume using a box model

Energy Tradeoffs Lab

Design electricity grid mixes and compare total CO₂ emissions, land use, and cost. Run decarbonization scenarios and explore the tradeoffs between nuclear, renewables, and fossil fuels

Groundwater Contamination Lab

Simulate contaminant plume spread through different soil types. Compare migration rates in sand, clay, and gravel, then test pump-and-treat remediation by placing extraction wells

Soil Conservation Lab

Measure how slope steepness and conservation practices affect erosion rates using the USLE. Progressively add cover crops, contour farming, terracing, and buffer strips to reduce soil loss

Earth History Lab

Calculate rock ages using radiometric dating with C-14, K-40, U-238, and Rb-87 isotope systems. Measure plate motion rates from magnetic reversal distances and predict future ocean widths

Nutrient Cycling Lab

Simulate nitrogen dynamics in agricultural soil with Euler-method ODE integration. Adjust fixation, nitrification, and denitrification rates, apply fertilizer pulses, and verify mass balance

Fertilizer Runoff & Eutrophication Lab

Model fertilizer runoff from farmland through buffer strips into a water body. Watch the eutrophication cascade from algal bloom to dissolved oxygen crash, and test buffer strip effectiveness

H-R Diagram & Stellar Classification Lab

Plot stars on a Hertzsprung-Russell diagram. Compute luminosity via the Stefan-Boltzmann law, classify spectral types (OBAFGKM), and estimate stellar lifetimes

Spectroscopy, Redshift & Hubble Law Lab

Explore emission and absorption spectra for hydrogen, helium, sodium, and more. Calculate redshift, recession velocity, and distance using Hubble's law

Exoplanet Transit & Habitable Zone Lab

Detect exoplanets using the transit method. Compute transit depth, orbital period via Kepler's third law, habitable zone boundaries, and equilibrium temperature

Moon Phases, Eclipses & Seasons Lab

Explore moon phases through the synodic month, eclipse geometry with node alignment, and Earth's seasons driven by axial tilt and solar declination

Telescope Resolution & Light Gathering Lab

Compare telescope designs by angular resolution, light gathering power, magnification, and field of view. Explore the Rayleigh criterion and compare refractor vs reflector optics

Weather Hazards & Safe Design Lab

Test building designs against weather hazards, apply the engineering design cycle, and discover which protection features reduce storm damage

Hurricane Path & Storm Surge Simulator

Set sea-surface temperature, wind shear, initial storm strength, coastal slope, and forward speed, then watch a hurricane track across the basin, intensify or weaken, make landfall, and generate a storm surge. Shows Saffir-Simpson category, central pressure, and surge height, illustrating how warm water fuels intensification and how coastal slope amplifies flooding.

River Flood Hydrograph Lab

Adjust rainfall intensity, storm duration, watershed area, slope, soil saturation, and urbanization, then watch the flood hydrograph respond. Compare a developed watershed against its natural baseline to see how impervious surfaces raise peak discharge and shorten lag time, using the Rational Method Q = C i A.

Water on Earth & Conservation Lab

Explore Earth's water distribution, trace the water cycle, and calculate how much water your household can save through conservation actions

Playground Design Challenge

Define a playground problem, set your design criteria, score three solutions, and recommend the best one. Grades 3–5.

Recycling Route & Community Helper Lab

Sort 10 waste items into recycle, compost, landfill, and special drop-off bins. Trace each item's journey and calculate how much waste you diverted from the landfill. Grades K–3.

Clean Water for Our School Mission

Investigate a contaminated water scenario, test 3 sample sites, and build a 2-step treatment chain. Compare filtration solutions by cost and effectiveness. NGSS 5-ESS3-1. Grades 3-5.

Constellations & Seasonal Sky Lab

Identify constellations in the night sky, explore which stars appear in each season, and trace star connection patterns. NGSS 5-ESS1-2. Grades 3–5.

Fast vs Slow Earth Changes Lab

Sort Earth events by speed, explore before-and-after change sequences, and simulate rock weathering through Rain, Wind, and Ice agents. NGSS 4-ESS2-1. Grades 3–5.

Landforms & Map Reading Lab

Identify major landforms, read a map using symbols and a key, and explore how elevation changes from sea level to a mountain peak. NGSS 4-ESS2-2. Grades 3–5.

Natural Resources & Conservation Lab

Sort renewable and nonrenewable resources, plan community conservation actions, and calculate your household resource footprint. NGSS 5-ESS3-1. Grades 3–5.

Reversible vs Irreversible Changes Lab

Sort physical and chemical changes, investigate clues to identify reversible changes, and explore how heat changes matter states. NGSS 5-PS1-4. Grades 3–5.

Sun, Shadows & Daylight Lab

Observe how shadow length and direction change across the day and between seasons as the sun moves across the sky. Grades 1-3.

Fossils & Ancient Environments Lab

Examine fossil evidence and match each fossil to its ancient environment. Discover what fossils tell us about Earth's past. Grades 3-5.

Weather Watcher & Clothing Lab

Test outfits against sunny, rainy, snowy, cloudy, and windy weather. Record correct, missed, and wrong choices to find which clothes work in which weather. Grades K-1.

Sun, Moon & Daylight Patterns Lab

Investigate predictable sky patterns. Record sunrise, sunset, daylight hours, and moon phases across seasons to find the patterns that repeat. Grades K-1.

Shadow Length Lab

Explore how shadow length changes throughout the day. Adjust the time of day and object height to see the SVG shadow update live, then record measurements and plot the results.

Soil Absorption Lab

Pour water on five soil types and measure how much is absorbed versus runs off. Investigate permeability, drainage, and how soil composition affects the water cycle.

Simple Weather Station Lab

Log daily weather observations over two simulated weeks. Record temperature, cloud cover, wind, and precipitation, then identify patterns across the 14-day period.

Greenhouse Effect Lab

Guided lab investigation of the greenhouse effect. Vary CO2 concentration from ice-age to high-emissions levels, record equilibrium temperatures, plot the relationship, and write a lab report with your findings.

Earthquake-Proof Building Lab

Design and test earthquake-resistant structures. Choose building height, width, and foundation type (rigid, base isolation, or dampers), set earthquake magnitude, run the simulation, and record which designs survive.

Volcano Eruption Lab

Investigate how magma viscosity and gas content control eruption type and intensity. Adjust sliders to vary basaltic to rhyolitic magma and dissolved gas percentage; the lab calculates VEI (0-8), eruption type (Hawaiian to Ultra-Plinian), column height, and names a real-world example volcano. An animated SVG cross-section shows eruption style with particle effects. Data table tracks trials for hypothesis testing.

Soil Layers & Permeability Lab

Investigate how soil composition affects water drainage using Darcy's Law. Build a soil column by adding layers of sand, loam, silt, and clay with adjustable thicknesses. The lab calculates effective hydraulic conductivity (harmonic mean), drainage time, Darcy velocity, permeability class, and runoff potential. An animated water-flow visualization shows drainage rate. Data table tracks layer configurations and drainage results.

NASA Climate Data Explorer

Explore real NASA POWER climate data (temperature, precipitation, solar radiation) for 20 cities worldwide. Compare trends across years, regions, and Köppen climate zones

Earthquake Feed Map

Explore real earthquake data from the USGS. Filter by magnitude, depth, and region. See the Pacific Ring of Fire and other plate boundaries light up with seismic activity

Weather Radar Analyzer

Analyze NOAA NEXRAD weather radar snapshots from famous storms. Identify hook echoes, eyewalls, bow echoes, and measure rainfall intensity with the Marshall-Palmer relation

Glacier Mass Balance Simulator

Set snowfall, summer temperature, and surface albedo, then run the simulation to watch a glacier advance or retreat. Track the equilibrium line altitude, accumulation area ratio, net mass balance, and the link to sea level.

Ocean Acidification Chemistry Lab

Raise atmospheric CO₂ and watch seawater chemistry respond. Track pH, carbonate and bicarbonate ions, and the aragonite saturation state that controls whether corals and shellfish can build their shells.

ENSO / El Niño Climate Simulator

Adjust the Pacific trade winds and eastern ocean temperature, then watch the El Niño and La Niña phases develop. Track the Niño 3.4 index, the tilting thermocline, and global rainfall teleconnections.

Wildfire Spread & Mitigation Lab

Set wind, humidity, slope, fuel density, and firebreak width, then run a cellular automaton wildfire and watch it spread across the landscape. Compare mitigation strategies and see whether the town survives.

Stellar Parallax & Distance Ladder Lab

Set a star's distance, the observation baseline, and the measurement precision, then measure its parallax angle and find its distance. See how parallax anchors the cosmic distance ladder and calibrates standard candles.

Galaxy Rotation Curve & Dark Matter Lab

Decompose a galaxy's rotation curve into visible matter and a dark matter halo. Tune the halo to fit the flat observed curve and see why visible matter alone cannot explain how fast the outer stars orbit.

Clean Air Filter Design Lab

Layer filter media to clean polluted air, then compare PM2.5 capture efficiency, pressure drop, airflow, clean air delivery rate, cost, and filter life. Discover why stacking more filters can choke airflow and why HEPA is not always the best choice.

Physics

Thermodynamics Lab

Build PV diagrams with isothermal, adiabatic, isobaric, and isochoric processes. Calculate work as area under the curve and explore Carnot cycle efficiency

Brownian Motion Lab

Track a particle's random walk caused by molecular collisions. Measure mean squared displacement and verify the Einstein relation connecting diffusion to temperature

Heat Transfer Lab

Visualize conduction, convection, and radiation with a temperature heatmap. Compare materials with different thermal conductivities using Fourier's law

Pendulum Lab

Measure pendulum period at different lengths to derive gravitational acceleration. Plot T² vs L, compare small and large angle behavior, and explore planetary gravity presets

Full Hooke's Law Investigation Lab

Run a full Hooke's Law investigation. Hang masses on a simulated spring, record replicated extension trials, derive the spring constant k from the slope of F vs x, and analyze residuals, %error, and the elastic-limit yield threshold

Full Projectile Motion Experimental Lab

Run a full projectile motion investigation. Three modes test optimal launch angle, R vs v² to derive g, and the effect of launch height. Replicated trials, regression, residuals, and percent-error analysis

Full Pendulum Investigation Lab

Run a full pendulum investigation. Choose one of three modes (period vs length, mass independence, large angle), record replicated trials, fit a regression line, derive g with uncertainty, and analyze residuals and percent error

Hooke's Law Lab

Hang masses on a spring, measure extension, and find the spring constant from the slope of F vs x. Calculate elastic potential energy and explore spring stiffness

Young's Modulus & Stress-Strain Lab

Pull a virtual wire of steel, aluminum, copper, titanium, bone, or glass and trace its stress-strain curve. Read Young's modulus from the elastic slope, find the yield point and ultimate tensile strength, watch the specimen neck and fracture, and compare the toughness of ductile and brittle materials.

Atwood Machine Lab

Two masses on a pulley system. Adjust mass ratio, observe acceleration, and verify Newton's second law. Compare theoretical and measured values with optional friction

Buoyancy Lab

Drop objects into fluid and observe floating or sinking based on density. Calculate buoyant force, apparent weight, and fraction submerged using Archimedes' principle

Standing Waves Lab

Visualize standing wave patterns on strings and in pipes. Adjust tension, length, and harmonic number to explore nodes, antinodes, and resonance frequencies

Diffraction & Slits Lab

Explore single slit, double slit, and diffraction grating patterns. Adjust wavelength and slit dimensions to see real-time intensity patterns with fringe calculations

Blackbody Radiation Lab

Adjust temperature to see Planck spectral curves shift. Explore Wien's displacement law, Stefan-Boltzmann power scaling, and the ultraviolet catastrophe comparison

Quantum Tunneling Lab

Explore quantum tunneling through potential barriers. Calculate transmission coefficients, visualize wave function probability density, and investigate how energy, barrier height, and width affect tunneling probability

Radiation Shielding & Half-Value Layer Lab

Place paper, aluminum, water, concrete, or lead shields in front of an alpha, beta, or gamma source and see how much radiation reaches the detector. Gamma rays attenuate exponentially through the half-value layer, while alpha and beta particles are fully stopped once the shield reaches their range. Graph transmitted counts versus thickness

Circuit Builder Lab

Explore series, parallel, and combination circuits with adjustable resistor values. Verify Ohm's law and Kirchhoff's laws with animated current flow and real-time calculations

Electromagnetic Induction Lab

Move magnets through coils, build AC generators, and explore transformers. Visualize Faraday's law with real-time EMF graphs and Lenz's law current direction

Friction & Inclined Plane Lab

Find static and kinetic friction coefficients by adjusting the ramp angle. Watch real-time free body diagrams update and discover the critical sliding angle experimentally

Momentum & Impulse Lab

Apply variable forces over time and see real-time force-time curves. Calculate impulse as area under the curve, compare to momentum change, and explore crumple zone physics

Geometric Optics Lab

Build ray diagrams for converging and diverging lenses and mirrors. Verify the thin lens equation, measure image distance and magnification, and classify images as real or virtual

Electrostatics & Equipotential Mapping Lab

Place point charges, probe electric potential and field at any location, and visualize equipotential contour lines and field arrows. Verify E = -dV/dr for dipole, quadrupole, and parallel plate configurations

Damped & Driven Oscillation Lab

Explore underdamped, critically damped, and overdamped motion with animated mass-spring-damper. Switch to driven mode to sweep driving frequency, find resonance peaks, measure Q factor and phase lag

RC/RL Transients Lab

Explore capacitor charging/discharging and inductor energizing/de-energizing with oscilloscope-style plots. Measure time constants, verify exponential models, and use semilog analysis to extract experimental values of τ

Gravity & Orbits Lab

Set central mass, semi-major axis, and eccentricity to animate elliptical orbits. Verify Kepler's Third Law, measure orbital velocity with the vis-viva equation, and compare circular and highly eccentric trajectories

Simple Machines & Mechanical Advantage Lab

Explore six simple machines with mechanical advantage, efficiency, and friction. Calculate effort force, distance ratios, and work for levers, inclined planes, pulleys, and more

Gear Trains & Power Transmission Lab

Explore gear ratios, compound gear trains, and belt drives. Compute output RPM, torque, and power for single-pair, multi-stage, and belt drive configurations

Hydraulics & Pascal's Law Lab

Explore Pascal's law, hydraulic presses, and hydrostatic pressure. Calculate force multiplication, mechanical advantage, and pressure at depth with interactive diagrams

Rotational Equilibrium & Torque Lab

Explore torque, rotational equilibrium, and angular dynamics. Place forces on a beam, find net torque, check equilibrium, and compute angular acceleration from moment of inertia

Mechanism Design Explorer Lab

Explore four-bar linkages, crank-slider mechanisms, and cam-follower profiles. Compute degrees of freedom, Grashof classification, transmission angle, and trace coupler curves

Magnetic Fields & Lorentz Force Lab

Explore B-fields from wires, loops, and solenoids. Calculate the Lorentz force on charged particles, cyclotron radius and frequency, and force between parallel wires

Gauss's Law & Electric Flux Lab

Apply Gauss's law to point charges, line charges, infinite planes, spheres, and cylinders. Visualize Gaussian surfaces, plot E(r), and explore how enclosed charge determines flux

Fluid Dynamics & Bernoulli Lab

Solve Bernoulli's equation and the continuity equation for pipe flow. Explore Torricelli's theorem, Venturi effect, Reynolds number, and airplane wing lift

Viscosity & Poiseuille Flow Lab

Change pipe radius, length, pressure difference, and fluid viscosity to see how the volumetric flow rate responds through the Hagen-Poiseuille law. Verify the fourth-power radius dependence (doubling the radius multiplies the flow by 16), watch the parabolic velocity profile, and check whether the flow stays laminar with the Reynolds number

Special Relativity Lab

Explore Einstein's special relativity interactively. Visualize the Lorentz factor, time dilation, length contraction, relativistic energy-momentum, velocity addition, and the twin paradox

Atomic Orbitals Lab

Visualize hydrogen atom wave functions with a 2D probability density heatmap. Plot radial probability distributions, explore energy levels, and investigate quantum number relationships

Magnets & Materials Lab

Test whether objects are attracted to a magnet, sort by magnetic properties, and investigate how distance affects magnetic force

Gravity & Falling Objects Lab

Predict which objects fall faster, run drop experiments with and without air resistance, and investigate how gravity and air resistance interact. NGSS 5-PS2-1. Grades 3–5.

Waves & Secret Messages Lab

Explore wave amplitude and wavelength, discover which materials waves travel through, and decode secret flash-code messages. NGSS 4-PS4-3. Grades 3–5.

Pushes & Motion Lab

Apply pushes and pulls to different objects and observe how force type, strength, and direction change motion. Collect data and discover Newton's laws in action. Grades K-2.

Circuits for Kids Lab

Test everyday materials to discover which ones conduct electricity and complete a circuit. Build a data table of conductors and insulators. Grades 3-5.

Light, Shadows & Materials Lab

Investigate how transparent, translucent, and opaque materials change the shadows they cast. Record shadow strength for glass, water, wood, fabric, and more. Grades K-1.

Communication Device Lab

Investigate how light patterns, drum beats, and cup-phone vibrations send messages over distance. Record patterns and decode signals across three device types. Grades K-1.

Sink or Float Lab

Predict whether 12 everyday objects will sink or float, then test them in a virtual water tank. Discover how density determines buoyancy and check your prediction score.

Magnet Strength Lab

Investigate how magnetic attraction changes with distance. Move a slider to change distance and record how many paperclips a strong, medium, or weak magnet attracts at each position.

Balloon Static Electricity Lab

Rub a virtual balloon to build static charge, then test attraction and repulsion with seven materials. Vary rubs and distance to discover how charge strength and distance affect force.

Paper Airplane Flight Lab

Design a paper airplane by choosing wing shape, nose weight, launch angle, and force, then fly it and record distance. Discover what variables make paper airplanes fly farther.

Friction Ramp Lab

Place objects on an inclined ramp, change the angle and surface material, and calculate whether the object slides. Investigate static and kinetic friction with Newton's second law.

Bridge Strength Engineering Lab

Design a bridge by choosing type, material, and span length, then load test it with increasing weight until failure. Discover how engineering design and materials affect structural strength.

Tower Stability Lab

Stack blocks of varying widths and offsets, compute the tower's center of mass, and watch it tip when the CoM passes the base edge. An earthquake force slider adds a horizontal load to test structural limits.

Rube Goldberg Chain Reaction Lab

Drag-place up to six machine elements (domino, ball, pulley, ramp, lever, spring) onto a chain, then click Run to watch each activate in sequence. Score is based on energy variety. Goal is to ring the bell.

Wind Turbine Blade Design Lab

Vary blade count, length, and pitch angle, then observe power output and efficiency. An animated spinning turbine and a power-vs-wind-speed curve show the Betz limit and optimal design principles.

Water Filter Engineering Challenge

Stack up to five filter layers (gravel, sand, charcoal, cloth, ceramic), pour dirty water through, and see cleanliness score and cost-per-liter. Compare designs using a data table and lab report.

Doppler Sound Lab

Observe how a moving sound source changes perceived pitch for a stationary listener. Choose from train, ambulance, race car, or fire truck sound sources. Adjust source speed and base frequency. Animated SVG shows approaching and receding wave compression and stretching. Displays observed frequency, pitch ratio, and wavelength ahead and behind the source.

Center of Mass & Balance Lab

Drag weights of varying mass onto a ruler to explore center of mass and tipping behavior. The ruler tips when the center of mass passes beyond the support point. Displays net torque, stability margin, and KaTeX formula for center of mass. Three difficulty presets guide progression from guided to open-ended exploration.

Pressure in Fluids Lab

Explore hydrostatic pressure using a U-tube manometer simulation. Vary fluid density (water, oil, mercury, glycerin) and depth to observe pressure changes via P = rho*g*h. Displays gauge pressure, absolute pressure, and pressure in multiple units (Pa, atm, bar, mmHg, psi). A fluid-height visualization shows the manometer response.

Rolling Motion Lab

Race four objects down an inclined plane (solid sphere, solid disk, hollow cylinder, hollow sphere) to see how moment of inertia affects rolling speed. Adjust incline angle and height. Displays acceleration, velocity at bottom, translational and rotational kinetic energy, and time to finish for each object. An animated race shows all four objects rolling simultaneously.

Energy Skate Park Lab

Animate a skater on three tracks (halfpipe, loop-the-loop, cosine hills) and observe real-time kinetic, potential, and total energy. Toggle friction to see energy loss per cycle. A live energy bar graph tracks all three energy values. Checks whether the skater can complete the loop and calculates the minimum height needed. Data table records energy readings across trials.

RC Circuit Charge Discharge Lab

Investigate how a capacitor charges and discharges through a resistor. Adjust resistance, capacitance, and source voltage with sliders. Plot V(t) and I(t) on a dual-axis chart with vertical markers at the time constant tau and at 5 tau. Compute charge stored Q = CV, energy U = 0.5 C V squared, and time to reach 90% of final voltage. Three guided experiments cover verifying tau = RC, energy stored vs voltage, and charge-discharge symmetry. Hypothesis, data table, and conclusions workflow with CSV and PDF export.

Newton's First Law Lab

Push a hockey puck across ice, wood, grass, sand, or a frictionless surface. Apply a brief force, watch friction slow it down, and discover how inertia and unbalanced forces shape motion.

Tower Strength Lab

Design a tower from wood, brick, concrete, or steel. Adjust floors, mass per floor, base width, and wind speed. Run real civil engineering checks for crushing and tipping.

Action-Reaction Lab

Two carts share a spring push-off on a frictionless track. Apply equal force in opposite directions and see how velocities, momenta, and energies behave when the masses differ. A high school Newton's Third Law lab with momentum conservation.

Balanced Forces Lab

Apply up to four forces at any angle to an object, change the mass, and see when the forces balance to zero or produce acceleration. High school Newton's First Law and equilibrium lab with full vector decomposition.

Simple Circuits Lab

Light bulbs in series, parallel, and with a resistor. Adjust the battery, toggle the switch, and watch current and brightness change in real time as you compare circuit layouts.

Optical Bench Lab

Place lenses and mirrors on an interactive optical bench and trace principal rays to find image position, magnification, and image type. NGSS HS-PS4.

Graph Analysis Lab

Probe slope, area, and intercepts on five AP-level physics graphs (v-t, F-x, P-V, I-t, x-t). Adjustable secant line and shaded area region with live numeric readouts and physical interpretation cards.

Biot-Savart Magnetic Field Line Visualizer

Visualize 2D magnetic field lines from current-carrying wires, loops, solenoids, and Helmholtz coils using the Biot-Savart law. Interactive probe with vector arrows and magnitude heatmap

Electric Potential 3D Surface Lab

Explore the electric potential V(x, y) from point charges as a 3D height map. Add, drag, and edit charges; toggle equipotential contours and E-field arrows on the floor plane

Fluid Flow Streamline Simulator

Interactive 2D potential-flow simulator: place circular cylinders, airfoils, and rectangles in a uniform stream with circulation. Real-time streamlines, drifting particles, and speed colormap

Solar Flare Tracker

Track real GOES X-ray flux measurements. Classify solar flares from A to X class on a log-scale chart. Explore the 11-year solar cycle and space weather impacts on Earth

Real Astronomy Sky Map

Explore the real night sky with the Yale Bright Star Catalog. Set your location and time to see which stars are visible. Identify constellations and find the planets

Fourier Transform Audio Visualizer

Real-time FFT analyzer with oscillator (sine, square, sawtooth, triangle) and microphone input. Waveform, frequency spectrum, and waterfall spectrogram update live

Polarization & Malus's Law Lab

Rotate two or three linear polarizers, measure transmitted intensity, and verify Malus's law I = I_0 cos^2(theta). Includes the three-polarizer paradox, polarized-sunglasses, and LCD-pixel demos. AP Physics 2, NGSS HS-PS4.

Build-a-Musical-Instrument Pitch Lab

Design a string, an open pipe, a closed pipe, or a water bottle, change the length, tension, and water level, then hear the pitch and read its frequency, musical note, and harmonic series.

Soundproofing Materials Lab

Test foam, fabric, cardboard, drywall, glass, vinyl, and lead as sound barriers. Set thickness and frequency, then compare transmission loss in decibels, cost per square meter, and which material blocks the most noise per dollar using the acoustic mass law.

Thermal Insulation Lunchbox Lab

Design an insulated lunchbox by choosing a wall material and thickness, then run the simulation to watch food warm up or cool down over time. Compare thermal conductivity, time constant, safe-keeping time, cost, and which material keeps lunch safe longest per dollar using Newton's law of cooling.

Statistics

Scientific Data Graphing Lab

General purpose data analysis lab. Paste a CSV, upload a file, or load a sample. Choose X and Y columns and fit a linear, quadratic, cubic, power, exponential, or logarithmic curve. Auto best fit picker, R squared, residuals, and shareable URL.

Graphs for Kids Lab

Build bar graphs from category data, read which groups have the most and fewest, compute the difference, and record findings to practice data literacy skills.

Mean, Median & Mode Lab

Enter number datasets, compute mean, median, mode, and range instantly, and record multiple datasets to discover when each measure of center best represents the data.

Hypothesis Testing Lab

Set up a one-sample z-test. Enter population mean, sample mean, standard deviation, and sample size. Compute the z-statistic, p-value, and decision to reject or fail to reject the null hypothesis.

Normal Distribution Lab

Set a mean and standard deviation, adjust a raw score X, and see the Z-score, percentile, and shaded bell curve area update instantly. Explore the 68-95-99.7 rule.

Line Plot & Fraction Data Lab

Place X marks on a fraction number line (fourths from 0 to 4), find the most common measurement, and record data to practice building and reading line plots with fraction data.

Spinners, Dice & Probability Lab

Spin a spinner or roll a die, track every outcome, and compare experimental probability to the theoretical 1/6. Discover how more trials bring results closer to the theoretical prediction.

Sampling & Randomization Lab

Compare SRS, stratified, cluster, systematic, and convenience sampling on a population grid. Detect bias, build sampling distributions, and watch standard error decrease with sample size

Bootstrap & Confidence Interval Lab

Draw bootstrap resamples to build confidence intervals using percentile, normal, and BCa methods. Run coverage simulations to verify that 95% CIs capture the true parameter 95% of the time

Monte Carlo Simulation Lab

Estimate π with dart-throwing, solve the birthday and Monty Hall problems, drop Buffon's needle, and trace random walks. Watch convergence plots approach true values over thousands of trials

Experimental Design & A/B Testing Lab

Design experiments with random assignment and blocking. Run A/B tests, compute Welch's t-test and Cohen's d effect size, and explore how sample size affects statistical power

Regression & Residual Diagnostics Lab

Fit linear, quadratic, and exponential models then diagnose fit with residual plots, leverage, Cook's distance, and Q-Q plots. Explore Anscombe's Quartet to see why R² alone is not enough

Logistic Regression Classifier Lab

Place two classes of 2D points, then train a logistic regression classifier with gradient descent and watch the decision boundary and cross-entropy loss curve evolve. Adjust the learning rate, compare separable and overlapping data, and see why a single straight boundary cannot solve an XOR pattern.

Categorical Data & Chi-Square Lab

Build contingency tables and run chi-square goodness-of-fit and independence tests. Compute expected counts, degrees of freedom, and p-values. Visualize contributions with heatmaps and bar charts

Exploratory Data & Distribution Lab

Enter data and compute descriptive statistics including mean, median, quartiles, standard deviation, skewness, and kurtosis. Visualize with histograms, box plots, and dot plots. Compare two datasets side by side

Bayesian Inference Lab

Apply Bayes' theorem with interactive probability trees and natural frequency grids. Explore the base rate fallacy, sensitivity vs specificity, and sequential updating

ANOVA & Experimental Design Lab

Perform one-way ANOVA with editable group data. Compute F-statistic, p-value, and eta-squared effect size. Visualize with box plots and an F-distribution curve

Central Limit Theorem & Sampling Distributions Lab

Draw samples from uniform, skewed, bimodal, and exponential populations. Watch the sampling distribution of means converge to normal as sample size increases

Population Demographics Explorer

Explore real demographic data from the World Bank and UN. Compare population pyramids across 30 countries and project future populations using growth models

Stock Market Statistics Lab

Explore real stock market data and compute returns, annualized volatility, Sharpe ratios, drawdowns, and correlation matrices. Test the random walk hypothesis and visualize fat tails

PCA Dimensionality Reduction Lab

Shape a 2D data cloud and watch PCA find its principal axes. Compare eigenvalues, see the explained variance, and project the points onto one axis to compress the data with minimal loss.

P-Hacking & Multiple Comparisons Lab

Run many hypothesis tests on random data and watch false positives pile up by chance. Apply the Bonferroni and Benjamini-Hochberg corrections to see how each controls error while keeping or losing power.

Misleading Graphs Lab

Learn to spot misleading charts. Identify truncated axes, cherry-picked ranges, and distorted scales, then compare each trick to an honest version of the same data.

Survey Bias Lab

Find the bias in real survey scenarios. Identify leading questions, non-response bias, convenience samples, and more, then choose a fix.

Correlation vs Causation Lab

Read a scatter plot and a claim, then decide whether it shows causation, reverse causation, a confounding variable, or coincidence.

Margin of Error & Poll Interpretation Lab

See how sample size sets the margin of error, why a small sample can represent a large population, and how to read a poll without being fooled.

Data Storytelling & Dashboard Lab

Judge whether a data dashboard honestly supports its headline, and flag the deception when it does not. A capstone for data literacy skills.

Computer Science

Cybersecurity Lab

Crack ciphers by brute force, measure password entropy, and explore the avalanche effect in hash functions. Collect data on how key length affects encryption security

Network Reliability & Fault Tolerance Lab

Test network redundancy by disabling nodes and links. Measure packet delivery rates, latency, and independent paths across star, ring, mesh, and tree topologies

Neural Network Playground

Configure a small neural network (hidden layers, neurons, activation function, learning rate) and train it on 2D datasets like spirals, rings, and moons. Watch the decision boundary bend into shape as a live heatmap while the loss curve drops, and see how a hidden layer separates data that a single straight line cannot.

Searching & Sorting Performance Lab

Compare linear search, binary search, selection sort, insertion sort, and merge sort side by side. Animate comparisons and swaps step by step, collect performance data across array sizes, and verify O(n), O(n log n), and O(n²) complexity

Selection & Iteration Code Tracing Lab

Step through Java code line by line with variable trace tables. Practice if/else selection, for loops, while loops, nested loops, and AP CSA-style code tracing with predict mode

Graph Theory & Networks Lab

Build graphs interactively, run BFS and DFS traversals, find shortest paths with Dijkstra, and compute minimum spanning trees with Kruskal. Analyze connectivity and Euler paths

Automata & Formal Languages Lab

Build regex patterns and test them against strings. Create finite state machines and step through transitions. Compare regex and DFA representations of the same language

Compression & Information Theory Lab

Encode text with Run-Length Encoding and Huffman coding. Build Huffman trees and compare compression ratios. Calculate Shannon entropy as the theoretical compression limit

Java Strings Lab

Explore Java String methods like substring, indexOf, compareTo, and charAt with a character-index grid. Trace through string algorithms including reverse, palindrome check, and Caesar cipher

Arrays & ArrayList Lab

Visualize array and ArrayList operations step by step. Trace through linear search, binary search, selection sort, insertion sort, and 2D array traversals with highlighted elements

OOP & Class Design Lab

Build Java classes with fields, constructors, and methods. Generate UML diagrams, trace object state through method calls, and explore encapsulation, inheritance, and polymorphism

Selection & Iteration Lab

Trace through if/else, for, while, and nested loops step by step. Evaluate Boolean expressions with short-circuit logic. Explore common patterns like accumulator, FizzBuzz, and multiplication tables

Boolean Algebra & Logic Gates Lab

Build and evaluate Boolean expressions, generate truth tables, simplify with Quine-McCluskey, and visualize logic gate circuits. Explore De Morgan's theorem and SOP/POS forms

Recursion & Data Structures Lab

Visualize recursive call stacks for factorial, fibonacci, merge sort, binary search, and tower of hanoi. Trace variable states and return values through each stack frame

Regex & Pattern Matching Lab

Build and test regular expressions with real-time match highlighting. Explore character classes, quantifiers, groups, and lookaheads with a plain-English pattern explainer

Number Systems & Data Representation Lab

Convert between binary, octal, decimal, and hex with step-by-step breakdowns. Explore two's complement signed integers, bitwise operations, and IEEE 754 floating-point representation

Big-O & Algorithm Analysis Lab

Compare growth rates of complexity classes from O(1) to O(n!), analyze algorithm performance with best/average/worst case breakdowns, and apply the Master Theorem to divide-and-conquer recurrences

Pathfinding & Heuristic Search Lab

Compare BFS, DFS, Dijkstra, and A* on interactive grids. Explore how heuristic choice affects search efficiency, generate mazes with different algorithms, and record path metrics

Data Structures & Tree Traversal Lab

Explore stacks, queues, linked lists, and binary search trees with visual operations. Perform and compare inorder, preorder, postorder, and level-order traversals. Benchmark structure performance

Debugging & Unit Testing Lab

Hunt bugs in code snippets, design test cases to catch defects, and classify error types. Track accuracy across difficulty levels and learn systematic debugging strategies

Coding Mazes & Sequencing Lab

Write step-by-step programs to navigate a robot through mazes, trace execution, and debug broken sequences

Loops, Debugging & Animation Lab

Compare flat programs to loop-based ones, fix buggy programs, and create event-driven sprite animations

Digital Citizenship & Online Safety Lab

Sort information cards into safe and private bins, respond to online safety scenarios, and take a digital citizenship pledge. Grades K–3.

How Messages Travel on the Internet Lab

Split a message into packets, route them through routers step by step, and reassemble them at the destination. Grades 2–5.

Computer Parts & Input/Output Lab

Identify computer parts, sort them into input, output, processing, and storage categories, and trace how data flows through a computer. Grades K–3.

Surveys, Charts & Data Stories Lab

Conduct a class survey, display results as a bar chart or pictograph, and answer questions about the data. Grades 2–5.

Variables & Scorekeeper Lab

Learn what a variable is, run step-by-step score programs, and design your own game. Watch values change as you add, subtract, and reset. Grades 3–5.

If/Then Choice Lab

Build IF/THEN/ELSE decision rules and test them with real-world scenarios. Discover how computers use conditional logic to make decisions. Grades 3-5.

Pixel Art & Secret Messages Lab

Paint pixel art on an 8x8 grid and encode secret messages with a letter-number cipher. Discover how computers store images and hide information as numbers. Grades 3-5.

Image Convolution & Filter Lab

Apply blur, sharpen, edge-detection, and Sobel kernels to sample images and watch a 3x3 window slide across the pixels. Inspect the convolution dot product pixel by pixel and see how each kernel transforms the image.

Cache Locality Visualizer

Traverse a matrix row-major versus column-major through a small LRU cache and watch hits and misses accumulate. See why the access pattern that matches the memory layout runs far faster.

Concurrency & Deadlock Lab

Run threads that take locks and update a shared counter, then step through the interleaving to watch race conditions lose updates and lock-ordering deadlocks form a cycle in the wait-for graph. Compare buggy and fixed versions.

Math

Matrix, Vector & Transformations Lab

Explore matrix operations, 2D linear transformations, and vector algebra with step-by-step solutions and real-time visualizations. Compute determinants, inverses, eigenvalues, projections, and more

Polynomial & Rational Functions Lab

Analyze polynomial roots, end behavior, and turning points. Explore rational functions with vertical/horizontal/oblique asymptotes and holes using interactive JSXGraph plots

Exponential & Logarithmic Modeling Lab

Model growth and decay with exponential functions. Compute half-life and doubling time, explore logarithmic inverses, and fit exponential and logarithmic models to data with R² comparison

Trigonometric & Polar Functions Lab

Explore sinusoidal parameters (amplitude, period, phase, shift), inverse trig functions with domain restrictions, and polar curve classification including cardioids, roses, limaçons, and spirals

Fraction Operations & Equivalents Lab

Explore fraction arithmetic with visual fraction bars. Add, subtract, multiply, and divide fractions and mixed numbers step by step. Find equivalent fractions and simplify to lowest terms

Ratio, Proportion & Percent Lab

Visualize ratios with bar models, solve proportions using cross-multiplication, and calculate percent change. Discover the asymmetry of percent increase and decrease

Integer Operations & Absolute Value Lab

Visualize integer addition and subtraction on a number line with directional arrows. Discover sign rules for multiplication and division. Explore absolute value as distance from zero

Equation Balance & Intro Algebra Lab

Solve linear equations with a visual balance scale. Apply inverse operations step by step, handle variables on both sides, and verify solutions by substitution

Place Value, Decimals & Scientific Notation Lab

Decompose numbers into place values with a color-coded chart. Convert between decimals, fractions, and percents. Express very large and small numbers in scientific notation

Probability & Combinatorics Lab

Explore probability rules with interactive Venn diagrams. Compute permutations and combinations with step-by-step formulas. Discover patterns in Pascal's triangle

Vector Spaces & Linear Independence Lab

Visualize span and linear independence in 2D. Row-reduce matrices to RREF step by step. Compute null space, column space, rank, and nullity. Verify the rank-nullity theorem

Quadratic Functions & Parabolas Lab

Explore standard, vertex, and intercept forms of quadratic functions. Find the vertex, axis of symmetry, roots, and discriminant. Complete the square and compare all three forms with an interactive parabola graph

Systems of Equations Lab

Solve 2×2 and 3×3 systems of linear equations using elimination, substitution, and Cramer's rule. Classify systems as consistent, inconsistent, or dependent and visualize intersecting lines

Function Transformations Lab

Explore how a, b, h, and k transform parent functions. Shift, stretch, reflect, and find inverses for linear, quadratic, absolute value, square root, cubic, and reciprocal functions

Exponents & Radicals Lab

Explore exponent rules including product, quotient, power, zero, negative, and rational exponents. See step-by-step simplification and radical-exponent equivalence with growth visualizations

Classroom Store Lab

Run a virtual classroom store - count coins and bills, calculate totals, make correct change, and explore money math with real-world shopping scenarios

School Schedule & Elapsed Time Lab

Build a school day schedule, calculate elapsed time between activities, and explore how duration relates to clock reading with interactive analog clocks and puzzles

Recipe Fractions & Mixing Lab

Scale recipe ingredient amounts using fractions, find equivalent fractions, and see proportional changes on fraction bars when halving, doubling, or tripling a batch

Measurement Detectives Lab

Measure virtual objects in inches and centimeters using an interactive ruler, convert between units, and display results on a line plot to find the mode and range

Garden Area & Perimeter Lab

Design garden plots on a square grid, calculate area and perimeter, and discover how different shapes can have the same area but different perimeters

Picture Graph & Bar Graph Detective Lab

Become a data detective! Build picture graphs and bar graphs from real class data, answer questions, and discover what the numbers show.

Volume City Builder Lab

Design buildings by stacking unit cubes, calculate volumes, and discover how different shapes can have the same volume. Complete city-building missions and compare 3D structures.

Shape Detective & Angle Hunt Lab

Hunt for angles in 8 different shapes. Classify each angle as acute, right, obtuse, or straight, then identify what type of triangle or quadrilateral each shape is.

Coordinate Treasure Maps Lab

Plot (x, y) coordinates on a first-quadrant grid to find hidden treasure. Calculate distances between locations using grid steps.

Decimal Operations Mission Lab

Complete story-based missions practicing decimal addition, subtraction, multiplication, and division. Estimate first, then calculate the exact answer.

Number Bonds & Fact Families Lab

Decompose numbers into two parts and discover all four related addition and subtraction facts. Record your findings and explore patterns. Grades K-3.

Hundreds Chart & Skip Counting Lab

Explore skip counting patterns on a hundreds chart. Record sequences, find patterns, and discover which skip counts reach 100 exactly. Grades K-3.

Calendar & Dates Lab

Investigate calendar patterns across different months. Count weekdays, find patterns in month lengths, and discover how the first day affects the whole month. Grades K-3.

Thermometer & Temperature Lab

Investigate temperature readings for different weather conditions. Record temperatures in Celsius and Fahrenheit and explore what each reading feels like. Grades K-3.

Nonstandard Measurement Lab

Measure objects with paper clips, erasers, and blocks. Discover how unit size affects the count and why standard units matter. Grades K-2.

Partial Quotients & Remainders Lab

Divide numbers using the partial quotients strategy. Record quotients and remainders, discover patterns, and understand what remainders tell us. Grades 4-5.

Bar Model Word Problems Lab

Use bar models to represent and solve word problems. Explore part-part-whole and comparison models and discover when each model helps most. Grades 2-5.

Ten-Frame & Subitizing Lab

Investigate how different arrangements on a ten-frame change how quickly you recognize a number. Record data and find the patterns that help you subitize faster. Grades K-1.

Count, Compare & Order Lab

Compare pairs of numbers and put sets of numbers in order. Record differences and look for patterns in how we decide which numbers are bigger. Grades K-1.

Teen Numbers Lab

Decompose every teen number from 11 to 19 into one ten and some ones. Investigate the place-value pattern behind numbers like thirteen, fourteen, and nineteen. Grades K-1.

Number Path & Hop Count Lab

Hop forward and backward along a number path from 0 to 20. Discover how adding and subtracting relate as opposite hops on the same path. Grades K-1.

Tally Marks & Pictograph Lab

Record survey data as both tally marks and pictographs. Compare which display makes it easier to answer questions like which is most or how many more. Grades 1-2.

Shape Sorter & Compose Shapes Lab

Classify 2D shapes by attributes and combine small shapes to build larger ones. Investigate how sides and corners relate, and how simple shapes compose into complex ones. Grades K-1.

Positional Words & Map Directions Lab

Investigate how spatial words like above, below, left, and right describe animal positions on a grid. Record position relationships and find when neighbors exist. Grades K-1.

Balance Scale Lab

Predict and test which everyday object is heavier. Investigate how size and material affect weight using a virtual balance scale. Grades K-1.

Ordinal Numbers & Sequence Lab

Investigate how ordinal numbers describe position. Record the 1st, 3rd, and 7th positions in animal line-ups of different lengths and find patterns from both ends. Grades K-1.

Area & Perimeter Design Challenge

Build fenced gardens on a grid and discover the relationship between perimeter and area. Fixed-perimeter mode: draw any shape with a given fence length and find the configuration that maximizes enclosed area. Fixed-area mode: minimize fencing for a given area. Isoperimetric inequality visualization with SVG grid, shape trace, and optimization leaderboard.

Measurement Conversion Lab

Practice measurement conversions with a hypothesis-first workflow. Estimate before you convert, then see step-by-step unit factor chain calculations. Covers 14 challenges across length (in/ft/yd/mi/cm/m/km), mass (oz/lb/g/kg), volume (fl oz/cup/pt/qt/gal/mL/L), and temperature (F/C/K). Data table records estimate, actual, and percent error for each challenge.

Chaos & Logistic Map Lab

Iterate the logistic map x next = r times x times (1 minus x) and watch a fixed point split into cycles and then chaos. Explore the bifurcation diagram, the cobweb plot, the Lyapunov exponent, and sensitive dependence on initial conditions.

SVD Image Compression Lab

Compute the singular value decomposition of a small image and vary the rank k to compress it. Compare the rank-k reconstruction, the compression ratio, the captured energy, and the singular value spectrum, and see why low-rank images compress better.

Calculus

Accumulation, Area & Volume Lab

Visualize Riemann sums converging to definite integrals. Compute area between curves and volumes of revolution using disk, washer, and shell methods with interactive cross-section views

Optimization & Related Rates Lab

Solve optimization problems with interactive diagrams showing the objective function and critical points. Explore related rates with animated geometry and chain rule applications

Differential Equations Modeling Lab

Draw slope fields and solution curves, step through Euler's method with error analysis, and model exponential growth, logistic growth, cooling, predator-prey, and mixing problems

Series & Taylor Approximation Lab

Apply convergence tests (ratio, root, p-series, alternating, comparison, integral), build Taylor polynomials with animated degree progression, and find intervals of convergence for power series

Limits & Continuity Lab

Explore the formal epsilon-delta definition of limits, apply the squeeze theorem, and classify removable, jump, and infinite discontinuities by testing continuity conditions

Derivatives & Tangent Lines Lab

Visualize derivatives as slopes of tangent lines, animate secant lines approaching tangents as h approaches 0, explore derivative rules step by step, and compute slopes on implicit curves

FTC & Net Change Lab

Explore the Fundamental Theorem of Calculus by building accumulation functions, evaluating definite integrals with antiderivatives, and computing displacement versus total distance from velocity functions

Parametric, Polar & Vector Lab

Trace parametric curves with velocity vectors, compute polar areas and arc lengths, and analyze vector-valued motion with speed, curvature, and tangential-normal acceleration decomposition

3D Vector Field Explorer

Visualize any 3D vector field F(x, y, z) with adjustable arrow density, color modes, and on-the-fly expressions. Read divergence and curl at any probe point. Eight physics presets

Geometry

Symmetry & Pattern Blocks Lab

Investigate lines of symmetry in 10 shapes. Toggle vertical, horizontal, and diagonal fold lines to discover which shapes have the most symmetry, then record your findings and look for patterns across regular and irregular shapes.

Angle Builder Lab

Build angles from 0° to 360° using a slider, classify each as acute, right, obtuse, straight, or reflex, and record data to discover the boundaries between angle types and the landmark turn angles.

Angle Relationships Lab

Investigate complementary (sum 90°), supplementary (sum 180°), vertical (equal), and parallel-line angle relationships. Set Angle A, observe Angle B, and record pairs to discover the numerical rules connecting each type.

Shape Classifier Lab

Explore 12 geometric shapes from triangles to circles. Inspect sides, angles, parallel pairs, and lines of symmetry for each shape, then record your findings to discover the properties that define each shape family.

3D Nets & Shape Folding Lab

Unfold six 3D solids into flat nets. Count vertices, edges, and faces for each shape, verify Euler's formula (V - E + F = 2), and record your data to discover the rule that connects all polyhedra.

Pythagorean Theorem Lab

Investigate the relationship between the sides of a right triangle. Adjust leg lengths, compute the hypotenuse, verify a² + b² = c², and identify Pythagorean triples by recording pairs and testing the rule.

Polygon Explorer Lab

Investigate regular polygons from triangles to 12-gons. Adjust the number of sides and measure interior angles, exterior angles, diagonal counts, and lines of symmetry to find the formulas that connect them all.

Congruence & Transformations Lab

Apply rigid motions (translation, rotation, reflection), test triangle congruence with SSS/SAS/ASA/AAS/HL criteria, compose transformations, and detect symmetry in polygons

Similarity & Triangle Trigonometry Lab

Test AA/SAS/SSS similarity, solve right triangles with SOH CAH TOA, apply Law of Sines and Cosines, and explore the ambiguous SSA case with interactive triangle diagrams

Circle Theorems & Tangency Lab

Explore inscribed angle theorem, Thales' theorem, intersecting chord products, secant angles, tangent perpendicularity, and power of a point with interactive circle diagrams

Geometric Constructions Lab

Perform 8 compass-and-straightedge constructions step by step. Build perpendicular bisectors, angle bisectors, parallel lines, equilateral triangles, and inscribed hexagons with verification

Coordinate Geometry & Conics Lab

Prove quadrilateral properties using coordinates (distance, slope, midpoint). Explore parabolas, ellipses, hyperbolas, and circles. Classify conics from general equations using B²−4AC

3D Measurement & Cavalieri Lab

Compute surface area and volume for 7 solid types. Slice solids with planes to see cross-sections. Verify Cavalieri's principle by comparing stacked slices of equal-area solids

Applied Math

Personal Budget Lab

Allocate income across expense categories, run a 12-month savings simulation with compound interest, and explore what-if scenarios like job loss, raises, and unexpected expenses

Wealth Growth Lab

Simulate wealth accumulation over 30+ years with employer matching, fees, and inflation. Compare early vs late start and low-fee vs high-fee investment strategies

Consumer Credit Lab

Compare borrowing costs at different APRs and terms. Test avalanche vs snowball payoff strategies on multiple debts. See the true cost of credit card minimum payments

Linear Programming Lab

Solve real-world optimization problems (factory production, meal planning, shipping) using the graphical method. Find feasible regions, evaluate corner points, and explore sensitivity

Measurement & Uncertainty Lab

Count significant figures, convert units, propagate errors through calculations, and chain dimensional analysis. Covers sig fig rules, error propagation formulas, and unit conversion tables

Decision Trees & Risk Analysis Lab

Build decision trees with chance and decision nodes. Compute expected values by folding back from outcomes, find the optimal strategy, and run sensitivity analysis on probabilities

Queueing & Bottlenecks Lab

Explore M/M/1, M/M/c, and M/M/1/K queueing models. Compute utilization, average queue length, wait times, and throughput. Visualize steady-state probabilities and identify bottlenecks

Materials Engineering Challenge Lab

Test real engineering materials across four challenges - shelter, bridge, insulation, and packaging. Score each material on strength, weight, longevity, and flexibility to find the best match

Build-It-from-Pieces Lab

Choose a base, add structural pieces, and test your construction for stability. Discover how shape, balance, and triangles affect how well structures stand up under load

Shade & Shelter Design Lab

Spend a 10-token budget on roof and wall materials to design a shade structure. Score your shelter on rain protection, sun blocking, and wind resistance

Paycheck & Taxes Lab

See how a gross paycheck becomes take-home pay after federal tax, Social Security, Medicare, and pre-tax deductions. Compare scenarios to see how raises and deductions change net pay.

Banking & Account Types Lab

Compare checking, savings, money market, and CD accounts, then match each saver to the best account for their goal. Covers APY, liquidity, fees, and FDIC insurance.

Insurance Basics Lab

Learn premiums, deductibles, coinsurance, and out-of-pocket maximums by running claims through a policy and comparing high vs low deductible plans.

Run a Business: Profit & Loss Lab

Set a price and quantity, then watch revenue, costs, and profit respond as demand changes. Find the break-even point and the price that maximizes profit.

Smart Spending & Comparison Shopping Lab

Practice smart shopping decisions using unit price, discounts, total cost, and needs versus wants, logging each decision to build good money habits.

Language Arts

Story Plot Arc Lab

Map a story's exposition, rising action, climax, falling action, and resolution on an interactive plot diagram. Record key events in each stage and analyze how structure reveals theme.

Figurative Language Lab

Tag similes, metaphors, personification, hyperbole, alliteration, and more across three passages. Click each sentence to identify the device type and record how figurative language shapes meaning.

Claim-Evidence-Reasoning Lab

Build structured arguments using the CER framework across three debate topics. Write a claim, add evidence with reasoning, acknowledge counter-claims, and measure your argument's strength.

Reading Strategies Lab

Practice active reading across three non-fiction passages. Make text connections, ask before/during/after questions, form predictions, and write summaries using guided strategy prompts.

Vocabulary in Context Lab

Infer the meaning of 18 vocabulary words across three themed sets using context clues. Identify the clue type, record your definition, then reveal the actual definition for instant feedback.

Reading Comprehension Lab

Timed reading practice with annotation tools and 6 passages. Answer scaffolded questions covering main idea, detail, inference, vocabulary, and author's purpose. Tracks accuracy across attempts for grades 6-10.

Narrative Writing Lab

Plan, draft, and revise a story through a three-phase workflow. Includes 10 story prompts, plot arc diagram, word count, reading-level estimate, and rubric auto-scoring across six dimensions for grades 6-9.

Argument Writing Lab

Evidence-based argument construction with claim, evidence library, counterclaim, and rebuttal scaffolds. Eight pre-built debate topics with curated evidence packets, peer-comparison mode, and rubric scoring for grades 8-12.

Poetry Analysis Lab

Mark up a poem for devices, scansion, and rhyme scheme, then complete a TPCASTT analysis. Five public-domain poem presets, 14 device tags, rubric scoring, and PDF lab report export for grades 9-12.

Grammar Patterns Lab

Practice identifying and correcting 10 grammar error types: subject-verb agreement, run-ons, fragments, comma splices, misplaced modifiers, and more. Bank of 33 exercises with fuzzy-match correction scoring for grades 6-10.

Essay Revision Lab

Practice revising real paragraphs. Find passive voice, wordy phrases, weak verbs, and redundancy, then compare your edits to a model revision.

Thesis Statement Lab

Sort weak and strong thesis statements against a 4-part rubric, then draft your own and check it against the same criteria.

Evidence and Commentary Lab

Match evidence to claims and write commentary that explains the connection, not just restates the evidence.

Tone and Mood Lab

Identify tone words and the mood they create, then swap a single word to see how diction shifts a passage's tone.

Sentence Combining Lab

Combine simple sentences using coordination, subordination, relative clauses, appositives, and participial phrases.

Grammar Error Detective Lab

Find and classify embedded grammar errors: run-ons, comma splices, subject-verb agreement, apostrophe misuse, fragments, and misplaced modifiers.

Social Studies

Civil Rights Movement Lab

Trace the American Civil Rights Movement from 1954 to 1968. Analyze 10 key events, identify causes and effects in a causal chain, and examine how protest and legislation created lasting change.

Ancient Civilizations Comparison Lab

Compare Egypt, Greece, Rome, Mesopotamia, China, and Maya across government, economy, religion, technology, geography, and legacy. Select up to three civilizations side by side.

Economic Systems Lab

Compare traditional, command, market, and mixed economic systems. Explore who controls resources, how prices are set, and design your own economy by adjusting five policy sliders.

World Geography Regions Lab

Explore and compare six world regions: North America, South America, Europe, Africa, Asia, and Australia/Oceania. Study area, population, climate, and culture, then test your knowledge with a quiz.

American Revolution Lab

Analyze the causes and key events of the American Revolution (1763-1783). Compare Patriot and Loyalist perspectives, rate the importance of each cause, and evaluate outcomes for five different groups.

Media Literacy & Source Reliability Lab

Evaluate sample sources on five reliability criteria - author, evidence, date, objectivity, and corroboration - then see a weighted reliability score, a verdict, and how your rating compares to an expert. Learn to spot misinformation red flags and practice lateral reading.

Archaeology Stratigraphy Lab

Excavate an archaeological dig site layer by layer, uncover artifacts, and use the law of superposition to order them oldest to newest. Estimate ages from depth and sedimentation rate, then practice telling evidence apart from interpretation.

Migration Push-Pull Map Lab

Explore why people migrate by adjusting push factors at an origin region (economic hardship, environmental stress, conflict, lack of opportunity) and pull factors plus barriers at two destinations, then watch the simulated migration flow split across the map using a push-pull model.

Trade & Comparative Advantage Simulator

Set how much grain and cloth two countries can produce, then compare life without trade to specialization based on comparative advantage. See opportunity costs, who should specialize in each good, and how trade raises total world output so both countries gain.

Supreme Court Reasoning Lab

Read landmark Supreme Court cases as cards, then sort statements into the facts, the constitutional question, the majority reasoning, and the dissent reasoning. Practice legal reasoning with Marbury, McCulloch, Brown, Gideon, Tinker, and Miranda using neutral plain-language summaries.

Public Goods & Free Rider Lab

Play a public goods game where each member of a group decides how much to contribute to a shared pool that is multiplied and split equally. See your payoff, the group benefit, and the marginal per-capita return, discover why free riding is tempting yet everyone contributing is best, and test policy fixes like mandatory minimums and punishment.

Gerrymandering & Districting Lab

Draw district boundaries over a fixed grid of Purple and Orange voters and watch the same votes produce different seat outcomes. Compare fair, packed, and cracked maps, see seat share versus vote share, and measure fairness with the efficiency gap.

Constitutional Amendment Process Simulator

Walk a proposed amendment through Article V proposal and ratification thresholds (two-thirds of Congress, three-fourths of the states) to see why most proposed amendments never become law.

Mock Election & Voter Turnout Lab

Set voter turnout for different groups, run a mock election, and log each result. See how turnout, not just opinion, decides who wins.

Citizenship Test Practice Lab

Take randomized practice tests of US civics questions in the style of the naturalization test, and track your score across attempts.

Founding Documents Comparison Lab

Compare the Declaration of Independence, Articles of Confederation, and US Constitution across purpose, power, and structure, then attribute features to the right document.

Jury Trial Deliberation Lab

Weigh the evidence in a fictional case, apply the standard of beyond a reasonable doubt, and reach a verdict. Learn how juries and trial rights work.

Constitutional Convention Compromises Lab

Explore the major debates of the 1787 Constitutional Convention and the compromises that resolved them, from the Great Compromise to the Electoral College.

Engineering

Truss Load Lab

Apply loads to a Pratt truss bridge and visualize the axial forces in each member. Color-coded tension and compression, support reactions, and zero-force member identification. NGSS MS-ETS1.

Beam Loading Lab

Place point loads and distributed loads on a simply-supported beam and visualize the shear force diagram, bending moment diagram, and support reactions. NGSS MS-ETS1.

Beam Deflection & Stiffness Lab

Load a cantilever or simply supported beam and see how far it sags. Vary the span, width, height, and material, then read the second moment of area, maximum deflection, bending stress, and factor of safety. Discover why a taller beam resists sagging far more than a wider one.

Thermal Resistance & Heat Exchanger Lab

Build a wall from conduction layers and convection films like an electrical resistance circuit. Add a parallel path such as a window, then read the total thermal resistance, the U-value, the steady-state heat-transfer rate, and a fluid outlet temperature. See why resistances add in series and which layer insulates best.

PID Control Tuning Lab

Tune the proportional, integral, and derivative gains of a PID controller and watch the closed-loop step response. See how P alone leaves a steady-state error, I removes it but can cause overshoot, and D damps the overshoot. Read overshoot, settling time, rise time, and steady-state error.

Pipe Network & Pump Operating Point Lab

Build a pipe network in series or parallel, set diameters, lengths, and friction, then define a pump curve and find the operating point where the pump curve meets the system curve. Uses Darcy-Weisbach head loss to show why a bigger diameter sharply raises flow and how series and parallel layouts compare.