Simple machine projects for the fourth grade focus on machines that have little or no movable parts and use energy to complete a task. The six most common elementary simple machine learning activities focus on inclined planes, pulley, screw, lever, wedge, wheel and axle projects. Lesson plans should incorporate hands-on labs or demonstrations with textbook lessons.

## Lesson Plans and Centers

When beginning a unit on simple machine, introduce new vocabulary words to the class. Students will need to understand the concept of a fulcrum, force arm, weight arm, velocity, energy and distance. Create center activities related to simple machines to reinforce what you teach in the classroom.

## Levers

Teachers can use common household materials to demonstrate how simple machines work to complete a task. Demonstrate how a lever works by using a scrap piece of board, textbooks and a juice can. Place the board on top of the juice can use the books to distribute weight. The weight arm of the board should be longer than the force arm. Add books to the force arm one at a time until the lever moves. Vary the spacing of the board and have the students record and compare how the position of the lever factors into movement of the weight.

## Pulley

Get creative with your simple machines projects to inspire student interest in science. Show student how to communicate with one another without cell phones. You can build a message pulley across the classroom and and allow each student a turn to pass a message. Use two pencils and two empty spools of thread to make a pulley for a string message line. Push the pencil through the spools and tie the ends of the string into a loop. Instruct a student to hold the pencil ends while the spool spins on the line. Another student holds onto the other spool. You have to wrap the string around the spools manually to make a simple pulley system. Each student can take a turn attaching a message to the pulley with a paper clip. A third students pulls on the string to make the message move across the room for delivery.

## Wheel and Axle

Use a pair of old roller skates to demonstrate how wheel-and-axle simple machines work. You can incorporate a lot of fun into the project by allowing students to move items with the simple machines on level ground, sliding board and up a concrete hill. Each students can bring an item to school to place inside the roller skate. Make a worksheet so students can record the results of the experiment. Students can weigh their items and measure the distance covered by the roller skate to compare the varying results.