Oh, yes, this in one hot little fantasy for sure. I liked it!

However, I think, you've told the story too much, rather than letting you and your characters have voices. Dialog nearly always seems to brings the written word to living breath realism so much more vividly.

E.g.

Homeroom has ended and the room is clear, I walk up to Mr. Simpson, ('who was' is past tense and superflous) my math teacher. Leaning over his desk I grin and ask him, "I was wondering, Sir, would you perhaps let me service you in exchange for a better grade?" (Maybe it's just me but I think 'service' is a bit dull, I would have used something like "suck your cock")

Mr. Simpson stifles a laugh but then his expression changes as he glares at me; "You're serious? Well, I think you may have some explaining to do, young lady—to the principal!"

"Oh, but I was just kidding, Mr Simpson, honestly!"

He smirks, "You thought you could get away with it, didn't you, you naughty girl?"

I stand back, hesitating, as I shuffle from one foot to the other. "But Mr Simpson…"

"The principal's office. Now!"