My high school is doing a distance-learning project with students from Russia along with the NASA center in Alabama. Our project is more of a mind exercise to see what we come up with, rather than something that will actually be used (although it could prove to be a lot of fun for astronauts!). Basically, our design team is a group of 15 kids from AP physics and chemistry classes; our goal is to modify an existing or create a new "toy" for astronauts to use in one of the following three places: the moon, mars, or the ISS. The "toy" can be aimed at any age group, there's not very tight restrictions--only that it be practical (to some extent). Obviously we want to take advantage of the microgravity. Building a toy to play with in the space station with no gravity opens so many possibilities, as does the 1/6 gravity on the moon and 2/5 gravity on mars. We would like to be able to build a prototype, but it is not required. What do you guys think would be fun to play with in space? Something that couldn't operate with Earth's gravitational force, but would be entertaining in a microgravity environment?