When you know more programming language than your teacher... but not because you're good, just because he sucks!
Reminds me of this question: it only happens once in a while or you had you guys experienced same feelling? How did you do to turn around that in your college?

I had this in high school, but I don't get it how can someone that isn't great get to be professor.
In my uni all of the professors are kind of great in their specialities.

If you say this about knowledge of syntax of some language or something similar, than it's not showing his programming skills...

not sure what "know more programming languages" sometimes isn't about quality than quantity? as long as your teacher can troubleshoot and explain when you get stuck, he's a good teacher