You have a crush on your teacher! Trust me, you're not the first one - male or female - to have that happen. Totally normal.
It's not possible to control who we become attracted to. Your body just reacts to that switch being turned on. We can only control our more obvious behavior. Why you feel something after hearing something cheesy is harder to understand. However, in our teen years, our bodies are adjusting to huge changes particularly hormones. We can get a variety of sensations, pain and pleasure without logical explanations. Nothing you are feeling is abnormal.
Hormones and the emotions are very tightly connected, and both are highly linked to the body. That's why we cry at seeing someone else in an emotional moment, like, in a movie when something touching happens. (Elsa the Lion comes back to see her family. Lassie comes home. The guy is waiting for Molly Ringwald at the church in 16 Candles.) That's why the body is able to get turned on by reading a sexy scene in a bodice-ripper novel.
People are biologically programmed to do one thing, produce more people. The goal of our genes is to replicate themselves. They will send you down whatever avenue, using whatever tools they have (hormones, emotions, nerve endings, etc.) to reproduce themselves, and right after puberty there is even more liveliness to all the signals. As AofA said, totally normal.
mmm i think this happens alot, actually i kinda had a little thing for a teacher in high school i probably coulda handled it better than i did though.... whenever she wore like a small shirt i couldnt stop looking at her breasts.... and skirts... man i used to have to my hand over my pants!