My teacher recently rejected the idea of me using this site for a research paper, and I was wondering if you would think that this site could be considered a source.
Your teacher was right to do so. This website would probably be a bad source to use as a primary reference in a paper. Any random moron in the world with internet access is free to post an answer here. (For exhibit A, click my name below...)
However, if there's something that has you stumped in your research, I'd think it would be an excellent place to try to get your questions answered. Good answers here should be sourced with hyperlinks, so it would also (hopefully) be useful for digging up other references that are usable. Use the references we supply to help jump-start your research.
T.E.D. gave a really good answer! Here are my bits on this:
If some answer in here really drives you in a new direction or brings up a new idea, you could of course give credit where credit should be given. Like "The following idea of sliced bread was brought up first by random moron in the world : Sliced bread is really a new thing, people have started to research it ." And give good sources in .
It's neither better nor worse than any other form of "PC - Personal Communication". Explain the idea in full, give credit where credit goes, and cite real sources. As with PC you should assume, that your reader has either no access to the source or will not trust it, so back your stuff with other things.
No, this website is not an academic source, in the same way that Wikipedia is not. Your first stop when asking a question should be the Reference Desk on Wikipedia. Anyone can answer there and you will find about as many incompetent fools as are here. However, Wikipedia's Reference Desk has a greater number of knowledgeable people -- including university professors of history, of whom there are none here -- than History Stack Exchange to point you in the right direction so that you can research an issue in depth. They also are more aggressive in handling trolls and extremists, which is a good thing.
SE is even worse than Wikipedia, because it doesn't have such tight quality control and answers don't even need references. It's as much an academic source as instant messaging with people who claim to be experts.