Writing at the advanced high school and college levels is largely about argument or rhetoric (a 'term of art' or more specific term for the same thing).

It might have been enough to have a thesis that was the equivalent of a main idea in the writing you did earlier in your academic career, but the emphasis will shift to originality as you progress.

So it isn't enough to write a paper that 'argues' that the drinking age should be lowered to 18, or the US should have never invaded Iraq. Those are both main points that could fuel a 4 or 5 page report (or an entire book), but they aren't original. What are you going to bring to the table to make your writing worth reading for your audience?

So argument is about originality. You need to support your original argument with evidence, clear writing, and skilled organization, but without the 'original' part you aren't going to get very far in any serious writing course.

We have combined some hard-won tips with a standard approach to explaining argument in the links below. Good luck!