Why do liberals believe that education is a right, not a privilege?

Education is a privilege, not a right. It is only a right in a communist state. In a capitalist one, only the best of the best deserve to be educated. Why should the poor have a right to education? If they want to educate their kids, then they should work for it so they can afford it. If they can't educate their kids, then they shouldn't have any. Really, it's all that simple. But liberals do not believe in the capitalistic values of our founding fathers. They want to turn us into a communist state.