Buxton Ridge Military Academy
The military school where Jake Morgendorffer was sent instead of high school (and possibly junior high as well).
There is no indication that his experiences were happy ones. He describes the other boys as bullies who could "smell" his fear. He describes himself as being demeaned and terrorized by Corporal Ellenbogen, one of the instructors (who is seen in a flashback). Also, Jake's family appears to have largely forgotten about him, leaving him there at the academy until he graduated.
Between these abuses and the general hardships of life there, and the fact that Jake described himself as a bed-wetter well into his teen years, the experiences he had at Military School were not pleasant. These shard negative experiences were the basis of a bonding moment between Jake and Anthony DeMartino.
Curiously, it is difficult to sort out to what degree Jake's memories are accurate. In real life, similar complaints are sometimes held over similar places or similar institutions. For example, the Blue Jackets Guard, basically a military version of the Boy Scouts. However, if Jake has proven us nothing else throughout the series, he has shown us that he is not necessarily the most reliable witness to his own life.