(covers information from several alternate timelines)
Medical school was an educational program in which entrants received medical tuition.
Leonard McCoy recalled practical jokes being played in medical school, such as trick glasses that caused one to spill one's drinks. After witnessing several such pranks at a senior staff dinner, he concluded they had a practical joker in their midst. (TAS: "The Practical Joker")
In 2263 of the alternate reality, Captain Kirk rhetorically asked Doctor McCoy, after McCoy made an insensitive comment about Kirk's father, if he had learned about bedside manner in medical school. (Star Trek Beyond)