Making an elevator is an appropriate science fair project for grades four through six. Using simple items, students can construct an elevator that demonstrates how a simple pulley system works to move an elevator up and down.
Construct the elevator car out of a small cardboard box. Punch four holes in the top of the box and two holes in the bottom of the box large enough to pass the string through.
Attach the spindles to the plywood board using the six nails. Arrange them so that four of the spindles are nailed across the top of the board and the other two are nailed to the bottom of the board exactly opposite the first two on the top of the board. The spindles at the top should be evenly spread at a distance of about four inches apart.
Tie one piece of string to the bottom of the box by passing it through the two holes and tying it off. Tie the other piece of string to the second two holes in the top of the box. You will use the first two holes in the top of the box to tie off the other end of the first piece of string in the next step.
Pass the string attached to the bottom of the box over the bottom two spindles and the first two spindles on the top. When you get to the first spindle on the top of the box, loop the string around it twice. Tie the end of the string to the first two holes on the top of the box once it's looped over the second spindle on the top.
Tie the second string on the top of the box and loop it around the remaining two spindles at the top of the box. Make sure the string it tight over these last two spindles and attach your counter weight to the end of the string.
Make sure all the strings are tight around all the spindles. Turn the second spindle with your fingers and watch as the elevator car moves up and down.