You see, "Not another Teen Movie" is, though the involvement of Phil Beauman and Buddy Johnson (Scary Movie 1), not like other spoof movies.
It is a satire of stereotypes seen in teen comedies or romances.
While other movies of the genre gain the humour with recreations of scenes or grossout humour, "Not another Teen Movie" also focuses on real jokes and tries to mock movies from both the 80s and the 90s/early 2000s.
Though not all jokes work and though there are funnier movies, "Not another Teen Movie" is definitely no waste of time.
Speaking of the age restriction, there is average teenage sexuality (masturbation, breasts exposed, lots of sexual talk,...) and very strong language.
Also typical, the teenagers drink a lot and smoke joints at one point.
All this is totally cliche and satirical.
What the MPAA does not say (and this is the most disturbing part in the movie):
There is one scene of strong gory violence.
A boy gets torn apart in half. (from left to right). You see his bloody flesh all over the ground while he still lives.
It is unexpected and will most likely shock older and younger viewers. It is meant to be comical, but it is not depicted like it.
The violence is other spoof movies is much less extreme.
I watched it at the age of 13 and i could not handle it. I watched it again, and i could handle it (perhabs because i knew what happens). If you watch it for the first time, i would not recommend it under the age of 15. That's the age where you might need to look away, but without being disturbed all night.
It is comical, though for it is extremely unrealistic. But if you have seen "Meet the Spartans" or "Vampires Suck" - which also had some rather strong comical violence - Not another Teen Movie's violence looks much more real than those and is more shocking. Absolutely not recommended to watch it unless you are an older teen.