2 things:

1. There’s actually an elaborated tax plan on Sanders’ website, including a description of which tax proposals are specifically intended to fund college tuition and agenda items. This particular plank in his platform entails a small type of capital gains tax. There’s also a pretty straightforward proposal to raise the marginal income tax rate, particularly for the top bracket (i.e. > $400,000/yr.).
2. The fight for economic justice looks like a steep uphill battle, but we’ve got to start somewhere. To accomplish something remotely resembling equality in our society will largely rest on our ability to realize economic equality, both as an ideal and as an actual practice. I honestly don’t mean for that to sound so pedantic (and I sincerely apologize if it comes off that way), its just the framework for my comments here and for my support of Bernie Sanders.