graduate funding sources

[Ideas]

How do they decide on scholarships?  I'd be happy to apply for some but also don't want to waste many hours without results.

I don't know that much about them personally, but I think many of them rely a lot on the essay. 

Some require community service, or letters of recommendation, but most don't seem to. One that don't require an essay usually seem to have letters / community service and other proof like that.

They often have a minimum GPA but it's usually not that strict, like 3.0, maybe 3.2, 3.3.