Watch this video of spoken-word poet Madiha Bhatti as she speaks about sexism in popular music: http://www.groundswell-mvmt.org/faithshare/listen-up-jay-z-this-muslim-womans-got-something-to-say-to-you/. After watching the video, write an 600-750 word argumentative essay and argue whether or not her points about the music industry are valid.
A thesis statement is a sentence or two that makes your provable point—what you are attempting to prove in your writing. Your thesis statement should take a stand. If your statement can be debated or disagreed with, then you have most likely made a worthy, arguable point. Your essays will be arguments not reports.
A thesis idea also takes a stand and makes a provable point. But it generally permeates the essay and is clear to the reader but does not make that statement in one sentence.
Either one, statement or idea, is acceptable. But, I will say that a thesis idea tends to be more challenging for beginning writers. If you tend to drift from your topic (nobody out there does that, right?), then I would suggest that you start with a thesis statement and work up to a more collective thesis idea later on.