The Curse of Heartwood Academy by Marty Chan

Fifteen-year-old Allie Lau is not excited to attend Heartwood Academy, a posh boarding school deep in a remote forest.

Subject to the whims of senior students, Allie faces an initiation ritual called the test, which requires her and other new students to spend the entire night in the forest. The senior students warn that a ghost lurks in the woods, preying on those who trespass. Allie braves the test, but when she accidentally kicks over a gravestone in an overgrown burial site, she finds herself pursued by some kind of zombie.