Purpose

To help students understand the timing of an engine and how the parts interact.

Materials

Model "valves" - paper rolled into tubes

Procedure

1. Assemble students in groups of five.
2. Assign parts to students - each group will have a crankshaft, piston, intake valve, spark plug, and exhaust valve.
3. Practice for a few minutes; teachers may observe and give tips.
4. Have groups perform in front of the class. Other students will critique the performances.
5. Award a prize to the best group.

Follow-up

Ask questions about the process. Demonstrate actions if applicable.

Suggested questions

Why is the crankshaft a necessary part of the engine?
How does the spark plug keep the piston moving?
What would happen if the exhaust valve opened after the intake?