Hello all, I don't normally post in this section but I figure this might be relevant to someone's interests.
In episode 23 of the anime (Located here
http://www.crunchyroll.com/sket-danc...rincess-583326 ) the whole episode deals with one of the protagonists and a recurring character (both female) drinking a potion and regressing to what looks like 3-5 year olds. Then a little bit later in the episode 2 other female characters regress. Then at the end all 4 get some AP, but something goes wrong and they age to about 27 year olds (10 extra years). The AP is pretty good, you get to watch their breasts develop and it isn't a poof. I'm pretty sure this hasn't been posted here before, doing a search for sket dance all that came up was a post about the manga from 2008.