Clothespin Math on a clothes hanger! Easy to make, and self explanatory. I'm thinking a wire clothes hanger would work better, so the clothes pins are easy to slide back and forth (almost like an abacus).
Tower of numbers: Each roll of toilet paper has a number on it. These toilet paper rolls will need to be placed in the correct order to create a tower. (Place a circle piece of paper between the rolls to make it easier to balance.