"To support the game I'm going to have the kids build terrain (mainly sugar cane fields), and each student will get to paint a 15mm Japanese figure"
Aren't there Child Labor Laws where you live!?!
Sounds like a great project! I wish that my kids' schools did something like this. Hmm...maybe I should ask the teachers.
Where are you located? If you're in the USA, I'll try to send brushes.