I've tried drawing Niels, Duncan and Natalie as teenagers before, but forgot to take into account when they were teenagers, so here is a second go.
Agent 250 grew up in the 70's on a ranch up north in one of the states the borders up to Canada, so his style is a mix of the fashion at the time and his ranch lifestyle. He was of course on the football team at his high school, where he also met Irene who was a cheerleader.
Agent 300 went to an expensive private school, so he proudly wore his school uniform when he hit town with his classmates. He was already quite the lady killer back then, and lured a lot of the girls home to let them ride his horse, which he only really had to impress the ladies.
Niels was a weird kid. He spend most of his time alone, but avoided getting bullied too much simply by creeping the other kids out.
Duncan was an orphan, and his uncle only provided him with a roof over his head but otherwise wouldn't even feed him, so Duncan quickly learned to steal to get by. He was extremely insecure, beat up anyone who looked at him wrong and always wore the latest fashion, which was all stolen or bought with stolen money.
Natalie was always up to date on fashion which didn't do her much good in 80's now that she looks back. She was a good kid and everybody had high hopes for her, so it was quite the punch in the gut for most when she started dating Duncan who had a horrible reputation.
Peter was already heavily into drugs and wore whatever the hell he could get his hands on. It was only later that he got a more hippie spirit.
Thomas was never super cool, and was a bit of a bookworm in high school. He wasn't uncool enough to get bullied but neither cool enough to hang out with the cool guys, and his teenage years went by unnoticed.
Irene was one of the popular girls at her high school, but not the bitchy kind. Her and 250 was the most popular couple and were voted king and queen at the prom.
Billy was a tomboy as you would expect, but she still hadn't completely accepted herself and was ashamed of being so masculine, so in an attempt to look more feminine she had her hair long and wore a bit of make-up. It didn't fool anyone though.