okay, so everyone talks about how human babies are pretty much helpless at birth and such. but have you considered the equally strange aspects of the teenage years. first of all you have to look at the social stigmas because they’re probably weirder than the biological stuff. teens are treated like sorta half adults, their expected to be independent but you cant vote, drive, buy certain stuff etc. for most of those years. also stereotypically teens are seen as overemotional and angry, to an alien this might make sense at first because of the hormone changes but then they also meet some kid who seems to be totally stable and confident, their crew mate brings up the other major stereotype that teen are all overconfident and annoying assholes.at this point the alien is just confuse because these two aspects conflict so much.
then they finally decide to ask some 15 year old what the fuck is going on. they tell them that what those thing they learned about behavior are just big assumption about a more complex situation. they also explain that everyone’s teenage years are different for everyone and so on and that older folks like to make fun of them for some reason.
but on the biological side things are weird too. some females start pubety as early as 9 and others at 14 while males do it later at 12-16. sometimes its really hard to tell how old a person is during those years. I’ve heard of a 14 year old being mistaken for 17 and a different person of the same age being mistaken for a 11 year old.
the aliens are just confused why we have such a weird growth period that has so many social stigmas attracted to it.