Children love hamsters and hot rods, so why not mix the two for a high interest math activity? Even the girls in my classroom loved this.
After hearing Hot Rod Hamster by Cynthia Lord, I had students cut hot rod counters and use them to model subtraction stories. This could easily be used for addition as well, if you want to teach the relationship between addition and subtraction.
A culminating project could be drawing a racetrack, gluing down some of the counters, crossing out the ones that "crashed," and writing a number sentence.