Grouping: Teams after individual module build
Take-home: Individual trigger module/photo + class machine experience
Key ideas: Energy transfer, cause/effect, reliability, interfaces, systems engineering.
Start with: Run a three-step chain where one unreliable transfer fails; ask students to diagnose interface.
Success check: Individual module succeeds 4/5 trials; team chain completes end-to-end.
Try changing: Ramp angle; trigger sensitivity; stored energy; handoff position.
Preparation: Define table zones and interface rule: each module must accept one input and create one output.
CNC preparation: Cut ramps, gates, base plates.
3D-print preparation: Print pulleys, guides, trigger latches if useful.
Lesson flow: Day 1: modules
Day 2: connect/test
Day 3: refine/final run
Video:
Design Squad Chain Reaction
Safety and cleanup: Safety glasses for stored-energy elements; soft projectiles only; establish a 'hands off during run' rule.
https://www.sciencebuddies.org/stem-activities/popsicle-stick-chain-reaction
https://www.youtube.com/watch?v=vblk7RIwa4A