Trying to recall a TV series (maybe a movie) set after the collapse of society. (Not zombies AFAIK, maybe nukes, or EMP or virus that killed the adults.) The show takes place shortly after the event, maybe a few months instead of a few years.
I believe the protagonists of the show/movie either live in the town or a nearby town. The people living in the in the high school (its former students) are trying to get the protagonists to join/help them.
Turns out a Cheerleader is running the school. She has sweet talked the nerds into getting the tech working again, by making wind generators, getting the water running again, fixing radios. She has gotten the jocks organized into guarding the school, scavenging the area for supplies and building fences around the school. She has gotten the other girls cooking/washing/organizing? (with maybe some of the girls being "rewards" for the guys to keep them working. Not sure about this.)
She has been bouncing back and forth between the groups trying to keep everything going smoothly, but I think it was slowly falling apart.
The series seemed to be more of a grim reality type show, like Jericho (2006) as opposed to a kids gonna rule if we can just get it right type show, like Daybreak (2019)
EDIT: Pretty sure it was a US series, so set in US, in a rural town. Maybe watched 10 years ago? Pretty sure it was after 2000.