High-school is great for learning new things and figuring out how capable of growing as a person you are in various pressure levels... but on a social note it's one of the most vicious times in a person's life. I did high-school years 1-4 in school and did 5-6 mostly from home due to illness at the time.
Now I'm in an apprenticeship for personal growth reasons, and it's terrifying actually being treated as an adult.
In highschool: "Miss, can I go to the bathroom?" "No, sit down."
"adulthood" literally 2 months after highschool ends: "Sir, may I use the bathroom?" "Yeah dude whatever you don't have to ask"
Not to mention the concept of like...being like...a standalone adult person...
