Ok, here we go. I'm ready to eat downvotes for this:
What a bunch of bias and misconceptions in the comments. I can't believe all of these uneducated rants, like gruseom's are getting so many upvotes.
1. The teacher knows VB.NET.
The main reason why the teacher might want to stick with VB.NET is because he knows it. He probably doesn't know a lick about Python at all. He's going to have a hell of a time answering questions about a language he doesn't know and isn't prepared to teach.
2. VB.NET != VB.
VB was syntax-massacred garbage. VB.NET is a pretty solid object-oriented language with a completely different but similarly English-like syntax. It's like damning Windows 7 for crap we haven't seen since Windows 9x.
I personally prefer C#, but people have written pretty basic VB.NET->C# parsers. VB.NET code pretty much cleanly correlates to C# structure and compiles to identical MSIL bytecode.
3. VB.NET teaches clean OO programming. Again, it's not the rat's nest than VB was at all. If you think C# is good OOP, then VB.NET is good OOP.
4. VB.NET is, in my opinion, much more approachable and useful to the average person. It's more "englishy" and most people run Windows PCs. People can very easily write native applications for their environment. They can in Python, with GUI toolkits, but its not as integrated or easy.
42. Ironically, I use Python and now avoid VB.NET work like the plague, but it's a solid option if you want to go that route. What's good for you and I ain't good for everyone. And PLEASE make sure you know what you're talking about before you click add comment on that masterful rant you just typed out.
You want a Python class? Suggest it to your school or teacher for next year. That will give them time to evaluate, and more importantly, prepare for the quest.