A few of my friends and I are planning a roadtrip and are doing so the cheapest way possible. We figured that going either north or west would be smooth sailing and would be away from all of the normal busy spring break spots. We thought of even going up to the dakotas, but aren't too sure.. What are some decent places to stop in on the way?? We have absolutely no idea where to go, or what places are worth going to.

We are driving ourselves, and have figured to just take I-80 most of the way, but that is all that we have figured out thus far. Cheap motels are the places to stay, even camping grounds are an option.
We are thinking thrifty here, so can anyone help us out?