Playing CrashPals together 🚂

CrashPals is a crash lab for ages 6–8. Two carts roll toward each other and clink together like train cars — and before the bump, your child guesses which way the pair will roll. The big idea: the cart with more push decides which way, and push is how big × how fast.

1 · Look at the carts

Each cart shows how big it is (its blocks) and how fast it's going (its arrows — or "still" if it isn't moving). Ask: "which one do you think is pushing harder?"

2 · Guess before the bump

Pick roll left, stop, or roll right. There's no penalty for a wrong guess — guessing first is exactly what helps the idea stick. Then tap Watch the bump!

3 · Talk about the push

After the bump, each cart shows its push number (blocks × speed). Count them together: the bigger number wins the direction; two equal numbers cancel and the carts stop. A little fast cart (push 2) can beat a big slow one (push… let's count!).

What it teaches

  • Force & motion: a moving thing pushes a still thing along.
  • Momentum, gently: "push = how big × how fast" — mass and speed both matter.
  • Predict-then-observe: the science habit of guessing, then checking.

We make no claim CrashPals raises test scores — it's an honest little physics lab. It runs entirely on your device: no account, no sign-in, nothing leaves your browser.

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