Ages and aging of the characters
First, I loved this movie when I first saw it in the early '80s to now. I was checking the age of the actors involved and was impressed that all the main stars were of high school age. Adam Baldwin & Joan Cusak were 18, Chris Makepeace and Matt Dillon were 16 and Paul Quandt was 14. That is pretty unheard of today or even in that day and age (i.e. Grease where the average high school students age was like 29).
I also think its funny how things change on how they age...case in point. Matt Dillon and Joan Cusak are 2 years apart and play classmates here, but in "In and Out", she played his former High School English teacher who was engaged to Kevin Kline's character (who was outed by Matt Dillon's character).
Just an observation.