Whatever you do, don’t be boring
There’s nothing worse than a boring cover letter. Okay, actually, there are a few things worse. You could spell the name of the company you’re applying to wrong, or just insult them. But, besides that, there’s nothing worse than being BORING. HR professionals read tons of cover letters every day. Believe me, that was once my full-time job. Very few cover letters stand out, and the ones that do are the ones that are interesting. Be interesting.
Note of caution. I say “be interesting”. I don’t say, “be TOO interesting.” There’s a fine line. You need to be professional and sell yourself, but you don’t need to be a comedian.
Since I used to be a teacher, here’s a link to an interesting article on cover letters for teachers: http://www.ethicsandnarrative.com/cover-letter-for-education-jobs