Wonderful show for preteens and up.
I really enjoy this show. I've watched 1 season and a few episodes of the 2nd. I do think you shouldn't let your kid watch it alone and here's why. Although you have a group of teens trying to become great dancers while finding themselves, big thing is their still learning. So they're going to make mistakes and get hurt just like any other teen. So it's important as a parent to make sure your son/daughter understands the consequences of the actions the characters do and why they shouldn't be mimicked. For example the character Kat, is very goofy, loves to be herself, and is very optimistic. Something a young girl would like to look up to. However due to Kat's home life, she doesn't fully appreciate how lucky she is to be at a privileged school. She treats her place sometimes as a joke and gets irritated when her friends don't want to goof off with her. She feels it's better to rebel and do what makes you feel good, rather than do what needs to be done. That's a great chance to talk to a pre-teen about personal responsibility, entitlement, and the importance of hard work. Also, Kat's mother is VERY neglectful, so it better explains why Kat acts the way she does.
What other families should know
Too much violence
Too much sex
Too much drinking/drugs/smoking