2 things that bothered me:
1. Does recess exist in middle school?
2. Where is this set where there are taxis everywhere?
Aftermath starts off as a compelling realistic fic/mystery set around a school shooting, with one of the alleged shooter's sister as the protagonist. She has an unrequited/unresolved love interest with the brother of one of the students killed in the shooting. They're both coming back to their local high school to face their fears.
This is written in the heightened reality of teen fantasy where no adults listen or can be trusted, so the teens have to solve everything themselves - not so heightened that it's ridiculous, but almost. he mystery drags in the middle, the teen "voice" is a little too "writer pretending to be a teen" and there's a fight scene that goes on way too long. A good choice to read when you want a thriller, don't want to think too hard, and enjoy kind of soap opera-ish narratives.