Interactive exploration
Cities & TransportTraffic jams and traffic waves
Why do traffic jams happen?
One driver brakes. A slowdown travels through the road. Find out how a small action can affect everyone behind it.
Cause & effect
Change one thing, observe what follows, and compare with a case where that change was not made.
Background on this ideaInteractive exploration
Machines & MotionGears and gear ratios
How do gears trade speed for turning force?
Turn once. Count what happens. Discover gear ratios, real-world uses, and why different jobs need different gears.
Interactive explorationScientific Thinking & Big IdeasCorrelation, causation and fair tests
Can the same pattern tell two different causal stories?
Investigate a virtual garden. Change who receives an assignment card, uncover a hidden starting difference, run fair trials and discover why a pattern alone cannot settle what caused it.
Interactive explorationComputers, Networks & AILanguage models and AI text
Where does a language model’s next token come from?
Open a genuinely trained miniature Transformer. Change token tiles, inspect real attention and vector calculations, sample a continuation, and test the limits of a confident prediction.
Interactive explorationComputers, Networks & AIMachine learning and training
Can a machine learn the wrong pattern?
Train a real classifier on editable inspection cards. Reveal a confident mistake, repair a misleading shortcut, and freeze your model before opening its reserved test.
Interactive explorationComputers, Networks & AICPUs and computer instructions
How does a CPU turn instructions into results?
Write a tiny real assembly program, watch values move through a processor’s logical parts, and stop at the instant an answer becomes stored state.
Interactive explorationComputers, Networks & AITransistors and electronic switches
How does an insulated gate control a current?
Inspect a connected CMOS cutaway, build a channel, find a circuit’s operating point and follow the charge and energy behind a changing bit.
Interactive explorationSpace & AstronomyBlack holes and light
If a black hole traps light, what are we actually seeing?
Inspect the real EHT observation, then choose a direction in a calculated light map. Follow its exterior path, find its source and reveal two images of one tiny patch.
Interactive explorationSpace & AstronomyRockets and propulsion
How can a rocket move when there is no air to push against?
Open a generic engine, follow what it carries and keep every bit of expelled mass in the story. Change who measures the motion, balance the thrust terms and discover what staging actually changes.
Interactive explorationSpace & AstronomyOrbits, satellites and gravity
How can falling keep a spacecraft above the ground?
Draw a velocity arrow, predict a path and compare two spacecraft on one clock. Follow a real NASA Earth map, inspect the next moment of free fall and discover why speed alone cannot make a circle.
Interactive explorationElectricity & EnergyNuclear fission and electricity
How does splitting an atom help make electricity?
Look through a power plant, follow three separate water routes and trace energy across their walls. Balance the energy account, then investigate why a growing average can still hide empty trials.
Interactive explorationEarth, Weather & ClimateEarthquakes and seismic waves
How can three stations help locate an earthquake?
Watch waves emerge from a buried source, pick synthetic arrivals and reveal the location one clue at a time. Test the clocks, depth and velocity assumptions—and compare the model with real recorded evidence.
Interactive explorationEarth, Weather & ClimateThe greenhouse effect
How can a planet warm without receiving more sunlight?
Freeze two model temperatures, change infrared transfer and release time. Follow every energy route, move the accounting boundary and compare the model with real atmospheric evidence.
Interactive explorationChemistry & MaterialsAcids, bases and the pH scale
Why is one step on the pH scale a big change?
Compare a hundredfold difference, transfer a tiny aliquot, turn a virtual burette and uncover why a weak acid and a strong acid reach different pH values at equivalence.
Interactive explorationChemistry & MaterialsSolids, liquids, gases and phase changes
Where does energy go while ice melts?
Give water an energy budget. Watch its temperature and phase masses, catch a melting plateau, compare two starting states and inspect an open ice structure.
Interactive explorationChemistry & MaterialsAtoms and chemical elements
What makes carbon different from oxygen?
Change particle counts, pin the differences, and discover what names an element. Then prepare one-electron hydrogen states, collect possible position outcomes and match energy gaps to light.
Interactive explorationBrain & SensesSleep and the body clock
Why do time awake and time of day both matter for sleep?
Change a fictional sleep history, catch the moment two curves meet, and separate a local clock change from a biological clock. Then follow light information from eye to brain.
Interactive explorationBody & HealthVaccines and immune memory
What can a vaccine leave behind after its ingredients are gone?
Open a protein-vaccine example, build a response with traceable cell lineages, and compare later encounters. Then follow the separate route from vaccine mRNA to a protein.
Interactive explorationBody & HealthThe immune system
How does a tiny intruder set a whole response in motion?
Explore how the immune system responds to an infection. Follow immune cells from skin to lymph node, inspect an antibody structure, and discover what immune memory leaves ready.
Interactive explorationBrain & SensesNeurons and nerve signals
How does a nerve cell send a message?
Nudge a membrane, discover when a spike appears, test its recovery, and cross a chemical synapse. Then inspect a real potassium-channel structure.
Interactive explorationCities & TransportAirplane wings and lift
How can a wing turn moving air into lift?
Run a virtual wind-tunnel test. Tilt a symmetric airfoil, probe both surfaces, and build the whole lift force from pressure around the wing.
Interactive explorationMachines & MotionCar differentials and transmissions
How do driven wheels take different paths around a corner?
Follow a transparent car around a bend, open its rear axle, and discover how a differential shares motion, torque and a low-grip limit.
Interactive explorationElectricity & EnergySolar panels and photovoltaic cells
Why does a solar panel’s power depend on what you connect?
Connect a realistic module to a virtual load, look inside a silicon cell, and build a day’s energy from changing light and time.
Interactive exploration
Electricity & EnergyElectric circuits
What does it take to turn on a light?
Close a switch. Follow a complete path. Give current a second route and discover what changes.
Interactive exploration
Physics, Light & SoundLenses and focusing light
Why does moving a lens bring things into focus?
Slide an object toward a lens. Follow the rays, find a sharp image, and discover the moment a camera becomes a magnifier.
Interactive exploration
Computers, Networks & AIThe internet and data packets
How does a message find its way across the internet?
Send “SMALL IDEAS!” through a network. Delay a piece, lose another, and watch what the receiver can actually use.
Interactive explorationEarth, Weather & ClimateThe water cycle
Where can a drop of rain go next?
Follow water above and below the surface. Pave part of the land, change evaporation, and watch the water budget rearrange.
Interactive exploration
Math, Probability & SystemsProbability and random patterns
How can random choices make a predictable shape?
Release a few virtual balls, then a thousand. Change the chance of a right turn and compare the results with a mathematical prediction.
Interactive explorationComputers, Networks & AIBinary numbers and logic gates
How do zeros and ones become a calculation?
Flip real input bits on a little calculator. Build a result from simple rules, and follow a carry as it crosses four columns.
Interactive explorationSpace & AstronomyMoon phases and eclipses
Why does the Moon seem to change shape?
Move the Moon around Earth and compare two viewpoints at once. Make a crescent, then tilt the orbit to discover why an eclipse is a special alignment.
Interactive explorationEarth, Weather & ClimatePlate tectonics and moving continents
How can moving rock leave a clock on the ocean floor?
Pull a ridge apart over millions of years. Read the age and magnetic pattern left behind, then compare spreading, sliding and subduction.
Interactive explorationEveryday TechnologyInsulation and heat transfer
How can insulation keep warmth in—and heat out?
Open a house wall. Swap its added layer, make it thicker, and reverse the temperatures to see why insulation helps in winter and summer.