There's something fishy going on here. I'm a student at Harvard, with a .harvard.edu email address, I didn't receive the sign up bonus. The best part is that I wrote in a complaint and they responded: "We've included the top 500 universities worldwide, but we can’t guarantee all domains are supported..." Not to boast or anything, but I think Harvard sits somewhere in the global top 500 universities...
I am, however, a phd student, so maybe that has something to do with it?