Edmodo: Will it be around in 5 years?

I am trying to figure this out. They have a lot of users however they have no business model. They have pledged to always be free and never have advertisements. Quote from their VP “Our pledge is that Edmodo will always be free for teaching and that we will never take advertising. That model doesn’t work for education.Source. So how will this company make any money? Well their plan is to develop and sell apps for teachers and students. However I believe they forgot one very important thing: Students and teachers are poor. They have no money. Teachers already have 2-3 extra jobs and pay for a lot of their own school supplies. I just do not see edmodo having any good plan that I can see at this point.