I've seen it with my youngest sister, who did poorly in a private school so ended up graduating from the local public high school. That was where she was put through the indoctrination process (the awful part is how many of a student's peers eagerly support the system and pile on the pressure). It is horribly effective, which is why we are at this point today.
Yes. One of the things I really like about being a senior citizen now is that I give a lot less of a crap about peer pressure.
But as a teenager, I remember it being a powerful force. You wanted to belong (at least I did, because I sure didn’t feel like I belonged...)