About CrashPals
Children push toy cars into each other long before anyone says the word "physics." CrashPals turns that exact moment into a lab: two carts roll toward each other and clink together, and before they bump the child guesses which way the pair will roll — then watches to find out.
Guess first, then watch
Every bump is a predict-then-watch puzzle: pick roll left, stop, or roll right, then set the carts rolling. Guessing first — even a wrong guess — is what makes the answer stick. Chug the marmot never scolds a wrong guess; he shows what happened and why.
The one big idea
Every bump comes down to push = how big × how fast (grown-ups call it momentum). The cart with more push wins the direction; two equal pushes cancel and the carts stop. A little fast cart can out-push a big slow one — and a big cart standing still has no push at all.
What it's good for (and what we don't claim)
CrashPals is gentle practice for force & motion — reading a collision before it happens. It is not a physics course or a brain-training app, and we make no claim it raises IQ or test scores. It's an honest little lab.
Safe by design
- On your device. Progress stays in your browser — no account, no sign-in, nothing sent anywhere.
- No dark patterns. No timer, no streak, no score to chase, and nothing to buy.
- Honest carts. Every bump plays out by real counting — the push you can add up is exactly what the carts do.