One thing that shows that Jerry is stressed is he's in a secret school society called the Vigils. Only selected students are allowed to attend to the society. It doesn't seem like him to be in that sort of group, he seems like he can be independent and doesn’t need people bossing him around, I think he's only in that group to feel important because when you’re a freshman not many people are aware of you and think you’re a nobody and they can do anything they want to you. In order to be officially in the group you must perform a task the "boss" tells you to do. Jerry had to unscrew all the screws in his classroom. He was doing it but he felt guilty and couldn't finish alone so he had some help.
Teens now a days are stressed out , whether its fro high school or just doing what your friends think is cool but you don;t and still end up doing it. A lot of things happen and are completly unexpected. I'm not going to write a 5 paragraph essay about why teens get stressed out becuase there are lots of reasons. In the book the Chocolate War that is one of the many reasons that Jerry is probably stressed out of, and Jerry is probably more stressed out than it even says in the book. Bottom line , teens have a lot of things to handle and get stressed out very easily.