Wow, the dude sounds pretty douchey.
I'd say if art is something you like to do or are passionate about then just do it, and ignore his view point on the matter. If you're feeling singled out on an unprofessional level by him, I'd suggest talking to the counselor if your school has one .
I was lucky in that my art teacher didn't have the word "bad" in her vocabulary. She was also a math teacher, which is weird, so she didn't really prioritize art or other subjects and never held us to any kind of standard.