There are two kinds of creativity. Sometimes you're creative for other people: for your teachers to get through school, to sell ad copy to pay the bills, etc. Sometimes you're creative for the art (or for yourself/your muse/however you want to see it). Neither kind is a wrong kind of creative, but one kind is infinitely more fulfilling.

You should feel free to push the boundaries. You should also feel free to point out to your teachers that you are going to write a Warhorse some day. They may not accept it right now, but some day they won't be able to stop you and if they don't want to recognize their fallacy in telling you to be practical over art forever (instead of just so you can be noticed), well you will graduate some day.