i work at a private school and the teachers dress business casual and dress down on friday's.. jean day lol.. it's free dress for the students every friday.
if a teacher is overdressed.. too professional looking i believe it'll be something for the kids to talk about.. i know when i was in school a couple of my girlfriends and i would aways laugh

lol. (whaat i was a young brat! lol)
but yea i think as long as they're not dressing like hoochies dressy pants/skirts is good enough.
i actually wear business casual clothes.. but im getting so tired of trying to find nice clothes that'll fit me (still having trouble getting this post pregnancy weight off).. i just want to wear my scrubs and lab coat lol