I think we made truly a fun activity. I wished that kids could have played with it. I can easily imagine kids playing with it for hours. Also, by setting the scores, we wanted visitors to manipulate the condition about the magnetic force in a thoughtful manner too. We thought about other representations for magnetic force.
Repulsion is also a very interesting phenomenon.
We finally came up with magnetic trees using doughnuts-like magnets with which visitors can try out attraction and repulsion. Mitchel pointed out that mathematical conditions are related to it. It could have been interesting if we had gone into that aspect. Even though what we tried to do is very simple, what is good about this exhibit is that it creates a surprising effect that children can hardly do at home. It also makes magnetic force a visible thing.