For you to do
Take something you built (a marble run, the saltwater battery, a folded bridge) and deliberately 'break' it — or fix one that already misbehaves. Your job is to find the ONE real reason it's failing.
Grown-up help
All on your own — this one is pure puzzle.
Hunt the cause
- Describe exactly what's wrong ('the marble stops at the second curve').
- Make ONE change and test. Did it help? Write it down either way.
- Keep going. Resist fixing five things at once — you won't know which one mattered.
What's happening
Push further
Write a one-line 'bug report' for your fix: what was wrong, what you tried, and the real cause you found.
This is **debugging**: the failure you SEE (marble stops) is usually not the **root cause** (the ramp is too flat there). Changing one thing at a time — **iteration** — is how engineers, coders, and scientists track a problem to its real source.