Help picking an appropriate citing style
Though I'm not a fan of it in general, in your case the IEEE style could work very well.  In the body of the paper, references are numbered in square brackets, like this: [1] and [2,3].  In the bibliography, you'd just have one entry per web page, with the URL.  If you use LaTex, it's easy to make these all active hyper links, so that your professor can click on the "[1]" to go to the bibliography entry, and then click on the URL to go to the StackExchange web page.  It's also possible to make the references hyperlinked in MS Word, but it might take some manual formatting steps to link each reference to each bibliography entry.