Some event causes security lockdown at school, spirals out of control as rights are taken away and students eventually disappear [s]

[Phylicia]

Basically, there is some event. A murder or bomb threat or something. I do not remember.

The administration puts in place new safety rules. No gang colors, no this no that. They send emails out to parents.

Rules gradually get weirder and stricter and you think the administration is just doing this because they can. It becomes unrelated to actual security.

Parents are for some reason still backing the school on it, and these emails about updates and rules keep going out.

Some good-for-nothings are "transferred" "expelled" or otherwise mysteriously disappear.

Main character kind of clues in that something is seriously wrong when a girl refuses to stop wearing something like a cancer awareness T-shirt (supposed "gang" shirt but it's obviously not) and gets disappeared with a lame excuse.

Students start disappearing in droves.

I forget the ending. I just remember that it wasn't dramatic. It was more along the lines of the student convincing his parents that they had to leave, and they just do so without telling the reader what was going on or providing closure.

[LauraW]

I remember a book like that, but I don't recall the name either. I'll check my book list.

[Andria]

After by Francine Prose?

[Shanna_redwind]

Variant has some of those elements, though not all of them. It's a high school with some weird rules and no obvious adult supervision and no way out. But there's no contact with parents.

[Phylicia]

Andria! YES! That is it. Thank you so so much.

And also a shout-out to Shanna who just gave me a new "to read" for my list.

[Andria]

You're welcome! Glad I could help. Here's the link: After. I'll go ahead and move this to "solved" and add the book to the group shelf for you.

[LauraW]

Yes, After is the book I was thinking of, too. Yay!