disenroll - Google SearchI've heard "unenroll" before but never "disernroll". Maybe it's regional.
I didn't take it as a challenge. I had to look it up myself before I posted it, so I already had the source up on my computer.Sorry, I should've been clearer. Didn't mean it as a challenge. I just don't recall it being used in an academic setting like enroll or unenroll in a class, etc. Now that you mention it, I may have heard it in regard to insurance coverage.
You can always make it more clear if needed.All in all, as per original question and mine, it seems that there is not much difference between retirar de la escuela for good and just for the day.