In the study group's first year at Greendale, Jerry and another janitor were trying to fix a broken water fountain in the school's hallway. While they took a break, a student named Troy Barnes happened upon the dismantled water fountain and started to repair it with one of their wrenches. Jerry and the other janitor returned and spotted Troy fiddling with their work. They yelled at Troy who fled the scene quickly. The other janitor tested the fountain and pointed out to Jerry that Troy easily fixed what they had been struggling to repair. Jerry was surprised and decided to track down the student. After finding out who Troy was he put together a scenario to test Troy. He put a cake outside a restroom to lure Troy in. There were no utensils or way to wipe his hands so this forced him to wash his hands inside the restroom. Jerry disabled the sinks to see if Troy could make them work again. As he expected, Troy easily repaired one of the sinks. Jerry made his prescience known by clapping and complimented Troy's abilities. He then handed Troy a card of a company and urged him to pursue a career in plumbing. Jerry told Troy that a stable career was preferable to the uncertainty of life after college. Troy ignored his advice because that he wanted to stay in college. After he left Abed came out of one of the stalls, washed his hands and said hello to Jerry.
Towards the end of the school year, Jerry accidentally came across a student at Greendale named Troy Barnes who seemed blessed with a natural gift for fixing things. He tested Troy and found him to be the real deal able to instantly size up a problem and repair it in an instant. Jerry didn't want to see such a great talent wasted and pleaded with Troy to pursue a career in plumbing. Troy didn't see this an option preferring to finish school. Jerry was disappointed by his decision feeling that it was Troy's true calling in life ("English as a Second Language").
In the study group's second year together at Greendale, Jerry is seen in the hallways of the school cleaning up the aftermath of the paintball war between Greendale and its rival City College. Still covered in orange paint and enjoying a soft drink, Abed finishes relating the story of how battle ended with Pierce saving the day. Jerry sarcastically mentions that they all seemed to have fun and Abed agrees replying he doesn't know how they will top it next year. Jerry suggests that instead of using guns next time they should use hoses. Abed tells him they already did that in the library and was surprised that Jerry hadn't seen it yet. Abed finishes his drink and looks around for a garbage can to dispose of it but Jerry tells him to just drop it anywhere. Abed then asks him if he has plans for the summer and Jerry tells him. Abed then leaves completely unaware at how angry the janitor is at the huge mess he has to clean up.
In 2012, Jerry once again tried to convince Troy Barnes to become a plumber. While he respected his original decision he wanted one more chance to prove Troy was a natural at this. Although Jerry managed to show Troy the joy of fixing things his display of talent brought Barnes to the attention of the Greendale Air Conditioning school. Jerry and the janitorial staff had a longstanding animosity with the AC repairmen and had a heated rivalry with them. He warned Troy to avoid them as he didn't want him to be exploited by a group he hated. However, his protégé disappointed him when after being offered a spot at the school by its Dean Robert Laybourne Troy actually considered it. Troy was impressed by the lavish lifestyle enjoyed by graduates of the AC repair school as opposed to the thankless tasks performed by plumbers. When Jerry asked him about this they got into an argument and Troy stormed off. Later in the year, Jerry and his co-worker Crazy Schmidt were cleaning up the Biology classroom when they made a disturbing discovery.
Jerry next appears in the study group's third year at school repairing a machine in the cafeteria. While waiting in the chow line, Troy sees his frustration at trying to fix the broken device and offers some advice. Jerry follows his directions and when he turns the machine on it starts functioning perfectly. Impressed again with Troy's abilities, Jerry then catches up to him. He tells him that while he respects his decision to remain a student over becoming a plumber, he wanted another chance to try and convince him otherwise. He asks Troy to meet him on the third floor men's restroom tomorrow and help him unclog a toilet; if he feels nothing for the work afterwards he'll never bother him about it again. Troy reluctantly agrees hoping to put an end to the matter once and for all. The next day, the two meet up in the restroom and having successfully fixed the toilet together Troy discovers, much to his surprise, that he enjoyed the work.
After admitting this to Jerry, they are both startled by the sudden appearance of a mysterious man wearing coveralls. He compliments Troy on his repairman skills which prompts a angry reaction from Jerry who yells at the man to go away immediately. He departs amused leaving a furious Jerry and a baffled Troy who asks the janitor what that was all about. With dead seriousness, Jerry grabs Troy and tells him that certain people will want to exploit his gifts and that he should only use his abilities for good. After he agrees, Jerry asks Troy to accompany him to the second floor restroom as someone wrecked the sink by pooping in it. Later that day, Jerry is concerned about Troy's welfare and visits the Group Study Room F asking the study group if they had seen him unaware that he had been kidnapped by the Greendale Air Conditioning Repair School. He later finds Troy at the "Gay Bash" where he is repairing the air conditioning unit.
He confronts Troy telling him that he should ignore everything the school promised him as he can have those same things by being a plumber instead. Troy questions why he is so against them and Jerry says it's because they are arrogant elitists who think they are more special then everyone else. This upsets Troy who angrily tells him that he is special and doesn't want to end up a loser like Jerry. A shocked Jerry is stunned by his response and and sadly watched as Troy stormed off ("Advanced Gay"). Towards the end of the semester, Jerry is seen with fellow janitor Crazy Schmidt cleaning up the Biology lab. While discussing the details of Schmidt's imaginary love life, he makes a shocking discovery. One of the Biology yam projects had been horribly smushed which ended up turning the classroom into a crime scene ("Basic Lupine Urology").
In the study group's fourth year at Greendale, Jerry and the rest of the school's custodial staff were having a "Murder Mystery" night during the day. Jeff and Troy interrupted their game and Crazy Schmidt who was dressed in drag yelled to kill the pair since they had seen too much. Jerry, who was dressed like Sherlock Holmes, explained what they were doing despite Jeff saying he'd rather they didn't know. Jeff then asked if they knew where a missing DVD of "Freaky Friday" he and Troy were looking for would end up if the custodial staff came across it in the study room. Jerry proclaimed his love of those type of body switching films much to Jeff's annoyance. He then explained that the DVD might have been put in the lost and found room. He led the pair to the room in question and before leaving warned them that amidst the mess to be found in there was a load bearing pile ("Basic Human Anatomy").
In the study group's fifth year at Greendale, Annie attempted to get a bulletin board that had fallen down in the cafeteria ("Introduction to Teaching") hung up. She enlisted the help of Professor Buzz Hickey. Hickey sought out Jerry's help who told him that he'd need to see the head janitor. Hickey gave up but Annie dragged him along to see Jerry, Crazy Schmidt and Carlo. After showing interest in them, Crazy Schmidt offered to put in a workorder for Annie. He indicated it'll take 3-6 business months to complete. When Annie asked if can be hastened, Jerry said she'll have to talk to a custodian. When Annie asked was the difference is, all the janitors showed disappointment.
("Analysis of Cork-Based Networking").