i don't know if it's out on dvd yet or ever... apparently it was released on showtime in april. anyway...
for the most part the movie fits the ideal of a campy musical (in a good way). it borrows the basic plot from the 1937 movie of the same name where an all-american 16-year-old boy is introduced to reefer by an unscrupulous dealer who claims to give him a special cigarette. in the 1937 movie his grades plummet and he ignores his girlfriend. the musical version includes a bizarre section where jesus christ tries to convince jimmy to give up the reefer and get high on the one true drug: god. jesus looks frighteningly like dave grohl but isn't.
the old version of the movie is in the public domain and available for download at various places. the musical's much more fun to watch though, simply because the old movie wasn't made to entertain