Harrington House is a building belonging to the Preppies on the Bullworth Academy campus. It is located southwest of the main school building, near the Gym and opposite the Auto Repair Shop. In the main storyline, it is only accessible to the player during the missions Weed Killer and Complete Mayhem; upon completing Chapter 5, however, it is possible to enter the building during free roam.
Harrington House was built for the Preppies' use, and was funded by Mr. Harrington, Derby's father. Its exact nature isn't clear. Dialogue in the game indicates that it is a private dormitory for the Preppies, but no sleeping quarters are seen in it and Preppies can be found in the Boys' Dorm with the other students if the fire alarm is pulled. It may just be an elaborate fraternity building. It has four stories and an elaborate series of tiered balconies. The first three floors are covered with fine art, including frat paddles, Knight's Armor, and plaques that can be torn off the walls and used as weapons. The top floor is a greenhouse which houses a rare giant Crapula Maxima venus flytrap.
Outside, the Preppies have a rather large paved lot in front of the building. To the right, there is a climbable tree that leads behind a wall to the area with the dumpster and a hidden path leading to the Gym. There is also a grassy lot to the left of the main building. Chad Morris's pet dog Chester lives in the lot and attacks most non preppies that go near it. Mowing the lot is also one of the detention tasks.
Due to a civil ruling, the preppies were forced to accept applications from students of lower income levels to use Harrington House. However, the Preppies were allowed to use their own criteria to decide which applications they accepted, and their criteria of choice was family earnings and genealogy. On the noticeboard, Chad and Gord offer to hire other students for menial labor, and later on, an invitation-only house party is revealed.
- Harrington House is based on Carrington House; one of eight boarding houses at Fettes College in Edinburgh, Scotland. Edinburgh is also the home of one of Rockstar's major studios, Rockstar North, famous for its role in the Grand Theft Auto series.
- Despite it being playing a huge role in contributions to the academy and on the Preppies' main turf, no Preppies are ever seen in it outside of missions.