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.