I am going to volunteer as an English teacher in Madagascar for two years, likely in a somewhat urban area. I will have free time and opportunities to lead secondary projects there. What should I do? I'm open to all opinions and advice—particularly on effective charities you know to be working in Madagascar.

My intent is to be guided by the community I'll be living in, but already I've thought about buying hippo rollers if my community needs to travel far for water.