I've used my student ID and so far no issue has been made about lack of inspiration date ... however, my ID has a transit sticker affixed to the front and is currently good through end of June. It's possible that this is mistaken for some sort of "proof of enrollment" through June 08. Alternatively, it would be easy enough to Photoshop some sort of "paid tuition" stub to stick on the back of your ID, like we used to have in the good old days.