Nate describes him as a drill sergeant without the uniform. He is rather mean to the students and makes them do wind sprints until they vomit.
John was born and raised in the small town of Botkins, Ohio. He had an imaginary friend, a koala bear named Ricky. John was an all-star goalie for his high school soccer team. He had 8 shut outs in his junior year and managed to get into the semi-finals before severely injuring his knee. He once mentioned that his coach in gym made him run until he passed out, thus making him call running until you vomit a "cakewalk." Suzy McCallister, who was his current girlfriend at the time, dumped him shortly after. He once married a woman, but she left him for a tennis coach.
P.S. 38 career
Coach John was Coach Calhoun's substitute when Calhoun had to go to a meeting about middle school PE. John said he did not like the things they were going to talk about, so he made the 6th graders do what he thought they should do: wind sprints. When the kids complained too much as they wanted to play a ball sport, he gave them a medicine ball.
Once, when Nate arrived late for gym, Coach John rushes Nate to change. When Nate comes back out of the locker room, he is seen wearing Coach John's clothes, looking like a mini Coach John. Coach punishes Nate by running wind sprints (while having a stomach full of green beans) and giving him a detention slip. On the slip, he called him "kid with weird hair" rather than his original name whilst hypocritically marking him for disrespect.
Sometimes, he would end up on duty at the playground or at the crossroad. He was doing the latter job while Nate attempted to convince Artur Pashkov to like Gina.
He also supervised the doodlers until Ken Rosa arrived. A few days later, he served as a chaperone at the Beach Party Dance.Coach John walked by while Randy is playing with the camera case. Randy calls his posse and orders them to form a wall to block him from Coach John's view. In Nate's "The Pathetic Misadventures of Randy Buttancourt" comic strip, Randy sees Coach John and tries to get rid of the evidence by flinging the camera up into the air.
Outside of P.S 38Coach John is also one of the assistant coaches in Coach Calhoun's Little League team, the Cream Puffs. He also coached lifeguard training, during which Nate accidentally pulled his toupee off. He is also the YMCA goalkeeper coach, and helped Nate fix his relationship with Kelly
John is known for his smelly armpits. His hair is revealed to be a toupee, and he is naturally bald. He is also obese, despite being a PE teacher.
Old fashioned techniques
Coach John is old fashioned, and he has several sports tricks and rules that are contrast to current rules, including