“A high school valedictorian who gets baked with the local stoner finds himself the subject of a drug test. The situation causes him to concoct an ambitious plan to get his entire graduating class to face the same fate, and fail.”
Trailer is bad quality, but I couldn't find it anywhere else...
http://teaser-trailer.com/movie/high-school
http://www.imdb.com/title/tt1247667/