I knew a guy who was an amazing programmer. Wrote his own operating system and did projects like real-time ray tracing and speech recognition while in high school. He decided to get his degree in physics specifically because he felt he already knew most of the CS stuff, but didn't know a lot about physics. His line of thought was why go to school to learn something you already know when there are so many things you don't know that they can teach you? That always struck me as a very clever way to look at things, and I've often wondered why more people who complain about how "easy" their CS courses are don't do the same.
Most classes are so big you can slip in there under the radar.
Dont wait or let some professor tell you can't take a course.
Get the reading material, do the assignments, and learn what you want.
My degree was in Maths/Comp-Sci, and as a result, I didn't have some of the courses I wanted open to me on CS due to clashes with compulsory Maths modules for some lectures. Me and a friend ended up sitting at the back of the 50% we could attend (on Networking), and doing a bit of work. After an interview with the prof we were allowed onto the subsequent modules that required the course, despite having never sat the exam...in his words, "It's your degree if you fail it.."
Study typing! Practice your high-speed essay-writing!
I don't know your situation, but: When they say "they won't let me take harder courses" does this mean they will physically throw you out of a random lecture if you attend one? Is there a rule against self-study? Does the library only let you check out certain books? Is your internet filtered? Keep in mind that I'm advising you to learn stuff, not necessarily get official credit for it. Transcripts are not very relevant. Nobody will glance at yours five years from now unless you apply to grad school.
Understand how lucky you are to be able to say "I have the option to get a degree... money is not a problem". Even if you are forced -- forced, I tell you -- to spend the next two years drinking beer, lounging around, and casually acing all your classes, do that rather than drop out at this point. IT jobs are not going anywhere. Silicon Valley is not going anywhere.
If money up front is not an issue you want a university degree. Even if considered as nothing more than a meaningless credential, university degrees pay off over time. More now than ever.
But it needn't be a mere piece of paper. If your classes are teaching you things you already know take different classes.
When you've studied physics up to field theory, biology through physiology and genetics, know how to build an amplifier from a tableful of chips, understand enough statistics to meaningfully criticize a published article in sociology or epidemiology, know how to use Photoshop to duplicate your favorite fancy website from scratch, understand music theory, have a grasp of linguistics and know some basic accounting come back and ask us what to do next. :)