Assembly line activity: a 40-minute paper boat factory, grades 6–8

1. Teach the fold once to everyone (8 min). Set the quality standard: a good boat has sharp creases and stands up on its own.
2. Round 1, craft shop (5 min). In teams of five, each person makes complete boats alone. Count only boats that meet the standard.
3. Plan the line (4 min). Split the folds into stations: fold in half, fold the corners into a hat, fold the flaps up, open and pull into a boat. The fifth worker is the inspector, who rejects any boat that doesn't meet the standard and hands it back.
4. Round 2, assembly line (5 min). Count passing boats and rejects.
5. Compare on the board: good boats per team, rejects, and good boats per worker. Ask: "Where did paper pile up?" That spot is a bottleneck. "How would you fix it?"
6. Round 3 (5 min). Teams redesign the line by moving a worker, combining two stations or adding a second inspector, then run it again.
7. Debrief: "Which round made the most good boats? Which job was most boring? Why might a factory rotate jobs, and what does that cost?" Talk about the trade-offs between speed, skill and quality.

Worth knowing: moving assembly lines spread through American car factories in the 1910s and cut the time to build a car from many hours to about an hour and a half. The idea is still used in factories, kitchens and warehouses today.

Differentiation: for students who need more support, assign them the inspector role with a picture of a good boat to compare against. For advanced students, have them calculate output per worker per minute for each round and graph it. For English learners, post station, bottleneck, reject and quality with a quick sketch. For students with fine-motor needs, give them the simplest fold, the inspector job or the timekeeper and data recorder role.

Quick check: "Your line made 20 boats in 5 minutes, but 4 failed inspection. What percent passed?" (80 percent.)

If you try it, post your class's best round 3 score and the change that got you there.