The vandergraph generator motor works off the principals of positive and negative charges. The vandergraph generator releases a positive charge at the bottom and a negative at the top. The bottom of the vengrpah generator is connected to a post on one side of the motor and the top of the generator to the other side of the motor. The motors' center is surrounded by different pieces of tin foil. Different pieces because they need to be charged separately. Brushes connected to the wires which go to the vandergraph generator are on either side of the motor center. One is negative and the other positive. The positive brush sends its charge to a piece of tin foil on the center of the motor. This charges the tinfoil to the same positive charge as the vandergraph generator and because of this it is repelled from that side. The same thing is going on in the negative side of the motor as well. Also the brush of the opposite side is attracting the other piece of tin foil. Thus the motor tuns and releases the charge and picks up another completing the cycle.