Dancing with Salt-Shannon and Stephane

The insulator (Styrofoam) was charged by friction and the conductor (pie tin) was not. That is why the salt sticks to the insulator and bounces off the conductor.
When a neutral object (the salt) touches the charged object(pie tin), the neutral object gets the same type of charge as the charged object. See, the salt bounced up and down between the pie tin and the table because the electrons were moving from object to object.
Later, we used an insulator (foam) and rubbed it with animal fur. As soon as we put it on the salt the electrons moved from the less electron object (the table) to the more electron object (foam) which caused the salt to sick.