A Strange Situation

The girl's were staying late at school. Madison finds a strange serum. The guys come in and she trips and the liquid splashes all over them. The guys are turned into children, and the girls ask their friend Madison Daniels for help.
( Not Madison Johnson, the girl in all of my other books.)
Madison will make a antidote, but will have a limited time to do so. Or the guys will be kids forever.