An inclined plane is a type of ramp. A plane is a smooth, flat surface that helps to move an object. One example of an inclined plane is a ramp that runs from the ground up to the back of a truck for loading heavy objects.
Have pupils use a small, flat board to create an inclined plane. They should find two base objects of different heights and place the ramp so that objects can be moved from one place to another.
A lever is an object that can be used to exert force on another object. For example, the claw on the back side of a hammer is a kind of lever because it can be used to pry loose a nail that has been pounded into a board.
Take a wooden board and hammer several nails into it. Ask pupils to apply the hammer's claw to remove the nails from the board. This will help them to better understand the way this simple machine works.
A wheel and axle is a simple weight-bearing machine that helps to move heavy or large objects. When the upright wheel is rotated, it causes the axle to turn, and vice versa. For example, wagons have wheels that are connected to an axle. When the wheels turn it causes the axle to rotate, and the wagon moves accordingly. Vehicles also use this system to support weight and create motion. Show pupils a diagram of a wagon or a vehicle wheel and axle to help them better understand how this machine works.
A pulley is similar to the wheel and axle except that, instead of an axle, a rope is attached to the wheel. This machine is used to lift heavy objects. A flagpole uses a pulley to raise and lower a flag. By pulling down on the rope or cord, you cause the flag to raise. Pulling the cord upward causes the flag to lower. If you have a flagpole at your school, take pupils to see it and show them how this simple machine works.