This is a really interesting article on the massive changes adolescent brains go through between 11 and 18.
It explains why brain changes can make it so hard for teens to get to sleep early - and get up early for school.
And how the bits of the brain develop at different rates - so the bits that govern decision making and future planning and consequences are temporarily less developed than the bits that want excitement NOW.
I often think it's connected to how humans might have only lived into their twenties in prehistoric times so nature is priming us to fight / hunt / breed NOW to keep the species going, which is why risky and rebellious behaviour happens at that stage.
And if parents had insights into why their newly teen child seems to have turned into a stranger, it's because they kind of have - a new person navigating the world with an evolving brain.
(I loved that film Inside Out, set inside a child's brain, and the end where a shiny new console is delivered with a big button marked Puberty 😁).
I think it would help parents hugely to understand why their teen behaves in such incomprehensible and trying ways.
https://www.fife.gov.uk/kb/docs/articles/education2/supporting-children-in-school/educational-psychology-service/teenagers-brains-and-behaviour