The Cheerleaders by Kara Thomas
First there was the car accident--two girls dead after hitting a tree on a rainy night. Not long after, the murders happened. Those two girls were killed by the man next door. The police shot him, so no one will ever know his reasons. Monica's sister was the last cheerleader to die. After her suicide, Sunnybrook High disbanded the cheer squad. No one wanted to be reminded of the girls they'd lost.
That was five years ago. Now the faculty and students at Sunnybrook High want to remember the lost cheerleaders. But for Monica, it's not that easy. She just wants to forget.
Only, Monica's world is starting to unravel. There are the letters in her stepdad's desk, an unearthed, years-old cell phone, a strange new friend at school. . . . Whatever happened five years ago isn't over. Some people in town know more than they're saying. And somehow, Monica is at the center of it all. There are no more cheerleaders in Sunnybrook, but that doesn't mean anyone else is safe.
Review from Kirkus Reviews:
Years after a series of horrific events left five young women from a cheerleading squad dead, the sister of one of them begins to suspect that justice has not been done.
Sixteen-year-old Monica is beginning her school year recovering from terminating an unplanned pregnancy after having a summer fling with a guy in his 20s. The physical and emotional pain that she feels is only compounded by the five-year anniversary of her kind and caring older sister Jen's death. Jen died by suicide, seemingly in reaction to two of her friends’ dying in a car accident and then, just weeks later, two others being brutally murdered by an obsessed neighbor, who was then shot and killed by Jen and Monica's police officer stepfather. However, Monica makes some discoveries that cause her to begin questioning this story, and she doggedly pursues each loose end she can find. The fantastical setup underpinning this contemporary mystery is intricate, and readers may struggle to keep track of all the characters as the narrative moves between the first-person present perspective of Monica and Jen’s third-person flashbacks. Yet, it cleverly layers a veneer of doubt over each of the players in the story, effectively keeping the audience guessing until the very end. Monica and her family are white, and there is diversity in secondary characters.
A busy, but satisfying, whodunnit with a solution as complicated as its premise.