Everything you need to understand or teach You'll Be the Death of Me by Karen M. McManus.
You’ll Be the Death of Me is a YA mystery by Karen M. McManus. When three former best friends decide to skip school just like they did way back in sixth grade, they stumble across the dead body of their classmate, Boney Mahoney. As the police arrive at the scene, the trio runs away and attempts to solve the crime before they can be implicated in the murder for being in the wrong place at the wrong time. But each character is holding back secrets from the others. The novel explores the judicial system, the media, family, friendship, and deception.