Overview: Ask questions to get the students thinking about machines. What is an engine? What is it for? Why do people use engines? What kind of engines do you use every day? Tell the students about the parts of an engine and for what they are used. During this, pass out an engine diagram for the students to color. As each part is mentioned, have them color the corresponding part on their diagrams. The parts to color will be pointed out. Spark plug - After a person turns the key, an electricall current is sent to the spark plug, which then ignites. The spark plug starts the pistons and makes the cycle turn. Gas tank - The fuel is stored in the gas tank. When the cycle is working, the fuel flows from the tank to the engine. Camshaft - The camshaft is a kind of "brain". It controls what valves to turn and determines which gasses and liquids to use. Valves - The valves are kind of like switches. They let the different gasses and liquids, such as exhaust and fuel, flow through the engine. Carburetor - The carburetor is the place where the gas mixes with air. Only regular gas would cause the entire car to explode, so air needs to be added to control the explosions. Cylinder - The cylinder is the place where combustion occurs. Piston - The piston goes up and down, depending on the stages of the combustion cycle. First, when the spark plug is activated, the piston explodes downward. Then the left-over matter, called exhaust, leaves, causing the piston to go upward. Then a new mixture enters, forcing the piston down. Finally, the piston compresses, and the pressure gets so high that the gasoline explodes, causing the piston to go downward. Then the cycle repeats. Crankshaft -The crankshaft is connected to the piston. When the piston goes up and down, the crankshaft rotates with a large amount of force. That force causes the wheels to turn. Perform the Flyswatter Game. Talk to the students about the systems and how the parts work together. Refer to the coloring worksheet described above. Intake - gas tank, camshaft, carburetor Exhaust - valves Energy creation (combustion) - piston, cylinder, spark plug Gas/air mixture - carburetor Movement of energy - crankshaft, camshaft Control - camshaft Re-explain what has been taught by reviewing the process again. Perform the Engine Acting activity.