I've been looking for a certain movie from my childhood for 18+ years now. Most of my memories of the movie is very hazy. It's set in high school or college. It has to do with a purple (I think that was the color) potion/drink that made people stronger/aggressive. The bottle looked circular and I think the cap was a quark. I've forgot the plot of the movie over the years and can't remember any of the actors. Only scene I can remember was someone hiding this drink behind a brick wall (behind a loose brick) in a classroom. I think the movie was kind of like "the in crowd". When you drank the drink it made you part of "the cool kids" but the draw back was that it made you aggressive. I believe it came out during the 80's or early 90's. Wish I could remember more about the movie but that's why it's been so hard for me to find it. Sorry for my description of the movie being so vague.
The movie is currently available on Youtube, and around 20:30, you can see the students finding the potion in glass bottles of prune juice hidden behind a brick wall: