"Daddy wants some chocolate!"
High School goes for a Superbad-with-stoners type of comedy, even going as far as casting discount Jonah Hill and discount Michael Cera in the leading roles, but it never finds the heart or the laugh-a-minute humour of that film.
However, on it's own merits, High School is pretty good for a stoner comedy. Not the funniest movie ever made, and it does have it's share of obvious and groan-inducing gags, but there are quite a few scenes and lines of dialogues that approach "classic comedy" territory, not to mention Adrien Brody's HILARIOUS performance as Psycho Ed.
It doesn't approach the heights of Up In Smoke, but it doesn't sink to the depths of Half Baked either. High School instead settles in the middle, providing undemanding laughs and fun performances for an hour and a half. And that suits me just fine.