This was the original title of "Reefer Madness".
From IMDb:
Believe the hype. This is one of the most hilariously over-the-top pieces of propaganda ever committed to celluloid. It's constantly unintentionally hilarious, especially Dave O'Brein's performance as Ralph.
So, what happens when a bunch of clean-cut teenagers (who strangely look like they're in their thirties) take one of puff of the evil vile devil's weed? They become homicidal perverted rapist dope-head fiends! There is so much useful information to be obtained from this film. For instance, did you know that marijuana is worse than cocaine? Or did you know how to hide your joints in your high heel shoes? Or that marijuana causes lifetime insanity? It's all here in this underground cult classic.