For Ages 9 to 11

Grades 4-5 Tools & Labs

22 interactive tools plus 8 investigation labs for Grades 4 and 5. Fractions, decimals, geometry, equations, ecosystems, energy, engineering design, and introductory computer science. Everything runs free in the browser.

22 tools 8 labs CCSS & NGSS aligned
Math Tools Math Labs Science Tools Science Labs Computer Science

Math Tools

Fractions, Decimals & Geometry

Master the core 4th and 5th grade CCSS math content: fraction operations, decimal arithmetic, area and perimeter, and factoring.

Fraction Operations Visualizer

Add, subtract, multiply, or divide fractions with fraction bar models, area models, and step-by-step solutions. Supports mixed numbers.

4.NF.3, 5.NF.1

Fraction Multiplication Visualizer

See fraction multiplication with colorful area models. Shade rows and columns to find the overlap, practice building models, and compare products on a number line.

5.NF.4, 5.NF.6

Fraction as Division & Sharing Stories

Share objects equally among groups and discover that the result is a fraction. Connect division to fractions through pizza, apple, and sandwich sharing stories.

5.NF.3, 5.NF.7

Decimal Grids & Tenths/Hundredths Explorer

Shade cells on interactive tenths strips and hundredths grids to build decimal understanding. Compare decimals visually and connect to fraction equivalents.

4.NF.6, 5.NBT.1

Decimal Operations with Base-Ten Blocks

Use base-ten blocks to add, subtract, multiply, and divide decimals. See flats, rods, and unit cubes come together with regrouping animations.

5.NBT.7

Area & Perimeter Explorer

Calculate area and perimeter of rectangles, triangles, parallelograms, trapezoids, and circles with SVG visuals and step-by-step formulas.

4.MD.3, 5.MD.5

Area Tiles & Perimeter Paths

Click to build shapes on a grid and see area and perimeter update live. Explore how shapes with the same area can have different perimeters.

4.MD.3

Factor Tree & GCF/LCM Calculator

Build visual factor trees, find prime factorizations, and compute GCF and LCM with a Venn diagram of shared prime factors.

4.OA.4, 5.NBT.5

Prime Factorization & Sieve Visualizer

Factor any number into primes with a branching factor tree and step-by-step division. Animate the Sieve of Eratosthenes up to 500.

4.OA.4

Bar Model Word Problem Builder

Build Singapore math bar models for part-whole, comparison, and multiplicative word problems. Visual problem-solving strategy for upper elementary students.

4.OA.2, 5.NF.2

Math Labs

Investigation Labs for Math

Structured labs with data tables and guided experiments for fractions, ratios, and place value concepts.

Fraction Operations & Equivalents Lab

Explore fraction arithmetic with visual fraction bars. Add, subtract, multiply, and divide fractions and mixed numbers step by step.

4.NF.3, 5.NF.1

Ratio, Proportion & Percent Lab

Visualize ratios with bar models, solve proportions using cross-multiplication, and calculate percent change.

5.NF.5, 5.NBT.3

Place Value, Decimals & Scientific Notation Lab

Decompose numbers into place values with a color-coded chart. Convert between decimals, fractions, and percents.

4.NBT.1, 5.NBT.1

Science Tools

Ecosystems, Energy, Earth & Engineering

Life science, physical science, and earth science tools built around the NGSS Grade 4 and 5 performance expectations.

Food Chain & Food Web Builder

Build food chains and food webs by connecting producers, consumers, and decomposers. See energy flow arrows and simulate what happens when a species is removed.

5-LS2-1

Ecosystem Matter Cycle Explorer

Interactive ecosystem model showing matter flow between sun, plants, animals, and decomposers. Build food webs and explore organism roles.

5-LS2-1, 5-PS3-1

Energy Conservation Explorer

Track kinetic, potential, and spring energy as an object moves along ramps, roller coasters, and spring systems.

4-PS3-1, 4-PS3-2

Simple Machines for Kids

Explore levers, ramps, pulleys, and wheel-and-axle with interactive simulations. Adjust parameters to see how simple machines reduce effort.

3-5-ETS1-1, 4-PS3-4

Rock Layers & Earth History

Explore sedimentary rock layers to read Earth history. Match fossils to time periods and discover how rock sequences reveal the past.

4-ESS1-1

Weather Hazards & Safe Design Builder

Learn about weather hazards like storms, floods, and wildfires. Match hazards to safety measures and design shelters to protect against extreme weather.

3-5-ETS1-1, 4-ESS3-2

Fossils & Ancient Environments Explorer

Match fossils to ancient habitats and discover what Earth looked like millions of years ago. Compare rock layers to see how environments changed over time.

4-ESS1-1

Trophic Transfer Explorer

Build energy pyramids and explore the 10% rule of ecological efficiency. Adjust transfer rates across trophic levels and compare energy, biomass, and number pyramids.

5-LS2-1

Science Labs

Investigation Labs for Science

Record data, form hypotheses, and export lab reports for engineering design, forces, and life science investigations.

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 planes fly farther.

3-5-ETS1-1, 3-5-ETS1-3

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.

4-PS3-1

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 affects strength.

3-5-ETS1-1, 3-5-ETS1-3

Soil Absorption Lab

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

4-ESS2-1

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.

5-LS1-1

Computer Science

Debugging, Data & Events

Build on sequencing and conditionals with debugging practice, data representation, event-driven programming, and variables.

Bug Hunt: Debugging for Kids

Find and fix bugs in short robot programs. Learn how programmers debug code by reading it step-by-step and testing to see where things go wrong.

CSTA 3A-AP-21

Pixel Art & Secret Messages

Draw pixel art on an 8x8 grid and see how images are stored as numbers. Encode and decode secret messages using the Caesar cipher.

CSTA 3A-DA-09

Event-Driven Animation Studio

Make a cat sprite react to clicks, timer ticks, and key presses. Build event rules by picking a trigger and an action, then create a 3-scene animated story.

CSTA 2-AP-13

Variables & Scorekeeper Studio

Create named score jars, build a step-by-step program with Add, Subtract, Set, and Reset blocks, then run it and watch the values change.

CSTA 2-AP-11

Standards Covered

  • CCSS Math 4: 4.NF (fractions), 4.OA (operations and algebraic thinking), 4.MD (measurement)
  • CCSS Math 5: 5.NF (fractions), 5.NBT (decimal operations), 5.MD (geometry and measurement)
  • NGSS Grade 4: 4-ESS2 (earth systems), 4-PS3 (energy), 3-5-ETS1 (engineering design)
  • NGSS Grade 5: 5-LS2 (ecosystems), 5-PS1 (matter), 5-PS3 (energy in organisms)

Mission Packs

Curated sets of tools and labs organized around a theme. Great for units or project-based learning.

Fractions Ecology & Environment

Looking for More?

Browse the full catalog of free interactive tools and virtual labs across every grade band and subject.

All Tools All Labs Standards Hubs