It doesn't matter if you're rich or poor, a university student or a secondary school dropout, white, black, Asian or orange, everybody deserves access to the diverse knowledge in the world. If you're a uni student like me you'll find these sites very resourceful. Even if you're not a uni student or graduate, then congratulations! The only fee you have to pay is the willingness to learn (trust me, it's miles better than having financial liabilities when you're barely at a quarter of your expected lifetime).
MIT OpenCourseWare - it's part of the OCW consortium and it's a massive collection of previous course materials taught at MIT. The learning resources are a bit sporadic though, and it ranges from partial lecture notes to full recorded lectures and textbooks, and the latter amount is not uncommon for "bricks and mortar" disciplines like mathematics and computer science.
Academic Earth - this site holds a collection of lectures and course materials from some of the top universities in the world, including Harvard, Yale and Oxford on a wide range of courses.
Open Culture - this blog has some a very extensive collection of free podcasts, ebooks and textbooks on various topics. If you're a documentary nut, you'll love the movie section. (John Wayne fans will love it too)
Well, hopefully at this point you don't feel overwhelmed and these will keep your summer pretty much occupied. Stay frosty!