Enjoyable movie for kids and adults. Very smart and accessible, and really nails some of the drama between young teens, challenges of relationships, and difficulties of raising a bored yet bright child.
It has a universal appeal to all younger viewers, but of note, all the main characters are women, and this works marvelously, from the outcast genius that wants to be accepted, to the makeup-wearing cool kids, to the single mom with her own set of challenges. This isn't to say it's a feel-good movie trying to make a political statement, but rather, it lets those characters be those characters and be believable. They have challenges like they would in real life, and every viewer will find someone to identify with at some level.
What makes this a good movie for kids is that one will always consider the choices made on screen, and wonder if those were prudent and the results of one's actions. While it's young teens playing it out, it applies to all the basic sensibilities to other life decisions, young or old.
(Disclaimer: I watched and enjoyed this movie several times, but I also worked on it as crew. I'm NOT paid for this review.)