The Preppies (or Preps) are one of the five school cliques at Bullworth Academy. Darby leads the clique, and Bif Taylor is his bodyguard and second-in-command. There seems to be no real hierarchy below that level, although Tad Spencer is seen giving orders in two missions and has aspirations to take over the clique.
The Preppies are the third clique in the hierarchy, above the Nerds and Bullies, but below the Greasers and Jocks.