The car that goes by itself
Explorers (Foundation), mission E1 Push, Pull, Roll, lesson 4 of 6.
Hook
This car has a secret spring inside. Pull it back and… whoosh!
Fair test
Pull back 1 hand-length, then 2. Which one goes farther?
Bonus challenge
Can you make it stop right next to a teddy bear, without touching it?
The build
🏁 Pull-back Racer: Pull it back, let it go — ZOOM! A racer with a spring for an engine. (level 2 of 5, about 12 minutes, 10 steps)