Read some information about levers.

A lever is a stiff bar that turns on a point, called the fulcrum. A lever trades distance for force or force for distance, that means you use less force over a greater distance or more force over a shorter distance.

Every lever has 3 parts:

1. Resistance Force or Load, or What you are trying to move or lift.
2. Effort Force or The Work done on the Lever.
3. Fulcrum or A fixed pivot point

There are different kinds of levers depending on the placement of the fulcrum:
The fulcrum can be between the force and what you want to move. (seesaw, crowbar)
The fulcrum can be at one end, the force at the other end, and what you want to move in the middle. (bottle opener)
The fulcrum can be at one end, the force in the middle, and what you want to move at the other end. (tennis racket)

Enter the Enchanted Learning site to find out about levers. The information is easy to read and has animations to show how the different types of levers work. Click on the wheel-barrow