Surprised that nobody here mentioned community colleges yet. Not a silver bullet, but the total cost of someone commuting to a community college from home is an order of magnitude cheaper than going to college. In many cases, CCs have explicit transfer programs, and the chances of transferring to a decent university after year two are pretty high.
I'm a product of the California Community College system and a lot of my teachers were teaching both in the UC and Cal State systems at the same time. I am happy with the quality of education I received.