My Rube Goldberg machine uses 4 out of 6 simple machine.First a ball (wheel) rolls down a ramp then goes in a tube (ramp) and goes in a toy truck (wheel) and the toy truck knocks over dominos (lever) and the toy truck rolls over and the ball comes out of the toy truck, the ball rolls down a ramp and goes down the screw (slide) and lands in the bucket.
