Honestly, none of them are that surprising. I can see explanations for all of it. Guy who got arrested 3 times cleaned up his act, and he really respected the cops because getting arrested helped him get better. So, he decided to become what he respected. Same for the girl who had academic trouble -- she probably has some great memories of a patient teacher helping her, and she grew up with a desire to help other kids who struggle. The genius was overconfident and he ruined his own life. The golden child thought he could get away with anything, and he couldn't. The nerdy D&D kid probably is interested in weapons and managing resources. Idk, I've never played DnD, but I'm pretty sure that it's a board game about swords and magic and gold pieces.
Anyway, my point is that a lot of this can make sense. Just gotta imagine them all as three dimensional people who can grow and change after high school, but who still have formative memories tied to their teen years.