College Board Advanced Placement
Tools and labs curated for College Board AP courses — Physics, Statistics, Biology, Chemistry, CS A, CS Principles, Calculus, and Environmental Science.
AP Physics 1 & 2
Kinematics, dynamics, energy, waves, optics, and electricity for calculus-based and algebra-based physics.
Tools
Forces & Free-Body Diagram Tool
Explore Newton's second law with interactive free-body diagrams on surfaces, inclines, and more.
Kinematics Solver
Solve constant-acceleration problems with step-by-step solutions and motion graphs.
Projectile Motion Calculator
Calculate trajectory, range, max height, and time of flight for projectile motion. Visualize the parabolic path with an interactive time slider and velocity vectors.
Energy Conservation Explorer
Track kinetic, potential, and spring energy as an object moves along ramps, roller coasters, and spring systems.
Momentum & Collision Simulator
Simulate elastic, inelastic, and partially inelastic 1D collisions with energy analysis.
Wave Explorer
Visualize transverse waves, superposition, interference, and standing waves.
Circuit Calculator
Calculate voltage, current, resistance, and power with Ohm's law. Build series and parallel resistor networks with step-by-step equivalent resistance.
Refraction & Snell's Law Explorer
Visualize refraction, total internal reflection, and critical angles with an interactive ray diagram.
Electric Field Visualizer
Place positive and negative charges on a canvas. See electric field arrows, field lines, and potential color maps update in real time.
Labs
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
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
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.
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
AP Statistics
Exploratory data analysis, probability, sampling distributions, inference, and regression.
Tools
Descriptive Statistics Calculator
Compute mean, median, mode, standard deviation, and more. Visualize data with interactive box plots and histograms.
Probability Distributions Explorer
Explore normal, binomial, Poisson, and uniform distributions. Visualize PDF/CDF plots, compute probabilities with draggable bounds, and find inverse values.
Normal Distribution & Z-Score Explorer
Interactive bell curve with shaded probability regions. Convert between raw scores and Z-scores with numerical integration.
Hypothesis Testing Calculator
Run z-tests, t-tests, two-sample t-tests, and chi-square goodness-of-fit tests. See test statistics, p-values, critical values, and step-by-step breakdowns.
Linear Regression Calculator
Find the best-fit line for paired data. See slope, intercept, correlation, R-squared, scatter plot, and residual analysis.
Regression Suite (Multiple & Polynomial)
Fit linear, quadratic, cubic, exponential, logarithmic, and power models to data. Compare R-squared, residuals, and predict new values with scatter plots.
ANOVA Calculator
One-way ANOVA for comparing 2-6 group means. F-statistic, p-value, effect size, summary table, and side-by-side box plots.
Chi-Square Test
Test independence with contingency tables up to 4x4. Chi-square statistic, p-value, Cramer's V, and grouped bar chart.
Central Limit Theorem Simulator
Draw repeated samples from non-normal populations and watch the sampling distribution become normal. Side-by-side histograms.
Labs
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.
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
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
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
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
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
AP Biology
Evolution, genetics, cellular processes, ecology, and information transfer in biological systems.
Tools
Photosynthesis Explorer
Explore photosynthesis rates under different light intensities, CO2 concentrations, and temperatures. See light response curves, compensation and saturation points, absorption vs action spectra, and the law of limiting factors.
DNA Sequence Explorer
Align DNA sequences with Needleman-Wunsch and Smith-Waterman algorithms. Translate codons, introduce mutations, compute Jukes-Cantor distances, and build UPGMA phylogenetic trees.
Cell Cycle / Mitosis-Meiosis Viewer
Interactive viewer for cell division. Step through every phase of mitosis and meiosis with SVG chromosome visualizations. Track chromosome number (2n vs n), see crossing over and independent assortment in meiosis, and compare both division types side by side. Presets for human (2n=46), fruit fly (2n=8), onion (2n=16), and simple (2n=4) cells.
Cellular Respiration Explorer
Explore glycolysis, Krebs cycle, and electron transport chain. Compare aerobic vs anaerobic respiration, calculate ATP yields for glucose, fat, and protein substrates, and see how temperature affects metabolic rate.
DNA Fragment Analyzer
Digest DNA sequences with restriction enzymes and visualize fragments on a virtual gel. Select from 10 enzymes, perform single or double digests, and estimate fragment sizes from band migration.
Labs
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
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
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
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
AP Chemistry
Atomic structure, bonding, stoichiometry, kinetics, equilibrium, thermodynamics, and electrochemistry.
Tools
Periodic Table Explorer
Interactive periodic table with all 118 elements. Search by name or symbol, compare elements side-by-side, and view by category, electronegativity, phase, or orbital block.
Balance Chemical Equations
Enter an unbalanced chemical equation and get integer coefficients, color-coded atom counts, and step-by-step verification that every element balances.
Molecular Geometry 3D Viewer
Select a VSEPR molecular geometry to see a 3D perspective SVG rendering with bond angles, lone pairs, and atom labels. Drag to rotate. Covers all 10 geometries: linear, bent, trigonal planar, tetrahedral, octahedral, and more. Includes preset molecules (H2O, NH3, CH4, SF6, PCl5).
Solution Chemistry & Colligative Properties Calculator
Calculate boiling point elevation, freezing point depression, osmotic pressure, and vapor pressure lowering for any solution. Supports water, benzene, camphor, and more solvents with preset solutions like NaCl, antifreeze, and IV saline.
Buffer & Titration Curve Explorer
Interactive titration curve tool for strong acid-strong base, weak acid-strong base, weak base-strong acid, and diprotic acid titrations. See real-time pH curve, buffer regions, Henderson-Hasselbalch equation, equivalence points, buffer capacity, and indicator color overlays.
Electron Configuration Generator
Look up any of the 118 elements to see full electron configuration, noble gas shorthand, orbital box diagram, valence electrons, and oxidation states.
Labs
Stoichiometry Lab
Identify limiting reagents, calculate theoretical and percent yield, and trace dimensional analysis step by step with visual mole bar charts
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
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
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
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
Thermodynamics Lab
Build PV diagrams with isothermal, adiabatic, isobaric, and isochoric processes. Calculate work as area under the curve and explore Carnot cycle efficiency
Reaction Types Lab
Classify reactions as synthesis, decomposition, single replacement, double replacement, or combustion. Watch animated molecular rearrangements and verify atom conservation
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
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
AP CS A & CS Principles
Object-oriented programming, algorithms, data structures, networks, cybersecurity, and computational thinking.
Tools
Java Array & ArrayList Explorer
Visualize Java arrays, ArrayLists, and 2D arrays step by step. Selection sort, insertion sort, binary search, and all ArrayList methods with animated operations and Java code.
Java Strings & Methods Explorer
Visualize Java String methods interactively. See charAt, substring, indexOf, equals, replace, and more with character-by-character SVG diagrams, == vs .equals() comparison, method chaining, and code tracing.
Class Design & Object Reference Explorer
Visualize Java OOP concepts with heap/stack memory diagrams. Create objects, make aliases, call methods, and explore reference semantics, scope, and inheritance with step-through execution.
Recursion & Call Stack Visualizer
Step through recursive function execution with animated call stack frames and recursion trees. Visualize factorial, fibonacci, merge sort, binary search, and tower of hanoi with memoization toggle.
Sorting Algorithm Visualizer
Watch bubble, selection, insertion, merge, and quick sort in action with color-coded bars for comparisons, swaps, and sorted elements.
Data Structure Visualizer
Visualize stacks, queues, linked lists, binary search trees, and min heaps with animated operations. Push, pop, insert, delete, and traverse step by step.
Pathfinding Algorithm Visualizer
Visualize BFS, DFS, Dijkstra, and A* on an interactive grid. Draw walls, set weighted cells, generate mazes, and watch each algorithm explore step by step.
Cryptography Explorer
Encrypt and decrypt messages with Caesar, substitution, Vigenère, XOR, and simplified RSA ciphers. Visualize step-by-step encryption, frequency analysis, brute force attacks, and hash avalanche effects.
Internet Routing & Packets Explorer
Visualize packet routing through network topologies. Animate Dijkstra's shortest path, explore TCP/IP layers, simulate traceroute, test fault tolerance by disabling nodes, and fragment packets.
Data Compression & Image Encoding Explorer
Explore Run-Length Encoding and Huffman coding for text, and pixel-level image compression. Build Huffman trees, paint pixel grids, compare lossless vs lossy compression ratios.
Labs
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
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
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
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
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
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
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
AP Calculus AB/BC
Limits, derivatives, integrals, the Fundamental Theorem of Calculus, parametric equations, series, and differential equations.
Tools
Limits & Continuity Explorer
Compute left-hand, right-hand, and two-sided limits numerically. SVG graph, approach table, and discontinuity classification.
Derivative & Integral Visualizer
Plot f(x), f'(x), and F(x) together. Drag a point to see the tangent line slope and accumulated area with step-by-step differentiation.
Polynomial Factoring & Roots Explorer
Factor polynomials up to degree 4 and find roots with step-by-step solutions.
Sequence & Series Explorer
Explore arithmetic and geometric sequences with terms, partial sums, and convergence analysis.
Differential Equations Solver
Solve separable, first-order linear, and second-order constant coefficient ODEs. Slope fields, solution curves, characteristic equation analysis, and step-by-step math.
Function Graph Explorer
Plot functions, explore properties, and see step-by-step derivative analysis with interactive graphing.
Labs
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
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
AP Environmental Science
Earth systems, living world, populations, land and water use, energy resources, and global change.
Tools
Population Growth Simulator
Simulate exponential, logistic, and Lotka-Volterra predator-prey population models. Interactive JSXGraph plots with carrying capacity, inflection points, phase portraits, and ecological presets.
Carbon Footprint Calculator
Estimate annual CO₂ emissions from transportation (car miles, fuel type, flights), home energy (electricity, heating, AC), diet (meat consumption, food waste), and lifestyle (shopping, recycling). Pie chart breakdown, country comparison bar chart, trees-to-offset and equivalent-driving metrics. Five presets: Average American, Eco-Conscious, Heavy Commuter, Frequent Flyer, Work from Home.
Atmosphere Explorer
Explore atmosphere layers, temperature profiles, pressure changes with altitude, temperature inversions, ozone chemistry, and planetary energy balance. Visualize the troposphere through thermosphere.
Ecosystem Matter Cycle Explorer
Interactive ecosystem model showing matter flow between sun, plants, animals, and decomposers. Build food webs, explore organism roles, and simulate what happens when species disappear.
Biogeochemical Cycles Explorer
Explore the carbon, nitrogen, phosphorus, and water cycles with interactive diagrams. Adjust human impact sliders to see how fossil fuels, fertilizers, and deforestation alter reservoir sizes and flux rates.
Weather & Water Cycle Explorer
Explore the water cycle with an animated diagram, predict weather from temperature/humidity/wind/clouds, identify cloud types, and compare seasonal patterns across climates
Labs
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
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
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
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
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
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.
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