Interactive labs
Explore interactive STEM labs
Every activity below teaches something real: physics, code, chemistry, or engineering. They run right in your browser, they're always free, and there's nothing to install or sign in to.
What's here
12 activities, grouped by subject. Jump to any of them, or scroll through in order.
Code & Logic
- Python PlaygroundWrite 10 lines of real Python and run it instantly. No install.
- Code-the-Path RobotDrag direction blocks to drive a robot to the goal flag.
- Logic Gate PuzzleSolve scenario-based circuits with truth table feedback.
- Sorting RaceWatch four sorting algorithms race the same numbers in real time.
Build & Test
- Bridge Load LabDrag a weight onto a truss bridge and watch it sag, stress, and snap.
- Block Tower PhysicsPull blocks, stack them on top, and try not to topple the tower.
- Catapult LabPick angle and power, fire the catapult, hit the targets.
- Marble RunPlace ramps and pipes so the marble drops into the goal cup.
Science Lab
- Atom BuilderAdd protons, neutrons, electrons. Watch the element change in real time.
- Circuit BuilderWire batteries, bulbs, and switches into a circuit and light it up.
- Density TowerPour liquids, drop objects, and find out who floats and who sinks.
- Gravity SandboxDrag to fling planets and watch them orbit, collide, or escape.
Code & Logic
Try it yourself
Real Python, right in your browser
This is real Python running in your browser with no install and no setup. Write some code, hit Run, and see what happens.
Run your program to see the output.
Computer Science
Program a robot to reach the flag
Stack movement blocks one after another, hit run, and watch the robot follow your instructions step by step.
Your program
Drag blocks here to build your program
Boolean logic
Match the truth table
Each level gives you a real-world rule and a target truth table. Pick one or more gates, compare what your circuit does row by row, then adjust until every output matches. Later levels chain gates and let you design your own table.
Read the scenario, choose your gates, and use the row feedback to fix the circuit.
How Logic Gates Work
Boolean logic is how computers make yes/no decisions. Every signal in a circuit is either ON or OFF, and each signal can also mean TRUE or FALSE.
A circuit has inputs, which are switches you control, and an output, which is a light that reacts. A logic gate is a small rule that looks at the inputs and decides what the output should be.
Try the switches below. Toggle them and watch how each gate decides the light's output.
Output turns On only when A and B are both On.
Output turns On when A or B, or both, are On.
Output is the opposite of the input.
Algorithms
Which sort wins the race?
Same shuffled bars, four different ways to sort them. Speed up or slow down to see how each algorithm thinks.
Like students lining up by height, it compares two neighboring bars and swaps them if they are in the wrong order. After many passes, the biggest bars bubble to the end.
Like sorting cards in your hand, it takes one bar at a time and slides it into the correct place among the bars that are already sorted.
Like picking the shortest person for the front of the line, it finds the smallest remaining bar, moves it to the front, and repeats.
It chooses one pivot bar, then sorts the other bars into smaller and larger groups around it. Then it sorts those smaller groups the same way.
Like splitting a big deck of cards into tiny piles, it sorts the small piles first, then carefully merges them back together in order.
Like making a pile where the biggest toy is always on top, it moves the biggest bar to the end, rebuilds the pile, and repeats.
Algorithm fact
Bubble and selection do roughly n² steps. Quicksort, merge sort, and heap sort are usually closer to n·log n, which is why they often pull ahead as the array grows.
Build & Test
How much can a truss bridge hold?
Add weight to the bridge and see how much it can hold. The triangles help spread the load, but too much weight will make the bridge fail.
Challenge
Get as close to the bridge limit as possible without breaking it.
Best safe load: 0 kg
Current weight
0 kg
Add weight slowly and watch the bridge deck. The goal is to get close to the limit while staying safe.
- Current weight
- 0 kg
- Bridge limit
- ? kg
- Safety left
- ? kg
Tower Stability Lab
Build to the goal line, balance the weight over the base, and keep the tower standing while the lab checks your design.
Level 1 of 26
First Line
Drag from the launcher and clear the near target.
Release the drag to fire. The gray path previews the shot.
Engineering
Guide the marble to the cup
Drop ramps and pipes onto the grid so the marble, released from the top, rolls all the way to the goal.
Level 01 / 15
First Turn
Place one ramp so the falling marble rolls across and drops into the cup.
Place one ramp so the falling marble rolls across and drops into the cup.
Rotate with R, erase with Delete, then launch the marble.
Science Lab
Chemistry bench
Build an atom, name an element
Add or remove protons, neutrons, and electrons. The number of protons decides which element you have. Try making oxygen with 8 protons. Oxygen is the element in O2 that your body uses from the air.
Known stable isotope · Neutral atom
Correct: neutral Hydrogen-1. 1 protons make Hydrogen, 0 neutrons make Hydrogen-1, and 1 electrons balance the charge.
Sandbox Mode
Explore freely. Every atom still uses the same validation as Challenge Mode.
Element
Hydrogen
Hydrogen-1
Atomic no.
1
Mass number
1
Charge
0
Type
Neutral
Protons
Positive (+). Decides the element.
Neutrons
No charge. Adds weight.
Electrons
Negative (-). Orbit the nucleus.
What changed?
Start with neutral Hydrogen-1: 1 proton, 0 neutrons, and 1 electron.
Electricity
Build a circuit that turns the lights on
Drop in batteries, wires, switches and bulbs. The bulb glows when current can flow in a loop from + back to −.
Chemistry
Stack a tower of liquids
Pour different liquids and they sort themselves by density. Drop objects in to see exactly where each one floats.
Choose a level
Badges
Astronomy
Build a tiny solar system
Click and drag in the sky to fling a new planet. Every body pulls every other one, just like in real space.
Higher mass means a stronger gravitational pull.
Missions
Pick a mission. Each one teaches one idea through launching, adjusting, and watching.
0 / 10
More games coming soon.
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