SALEM, Mass. (AP) -- A 14-year-old Massachusetts boy is set to be arraigned on murder, aggravated rape and armed robbery charges in the killing of his high school math teacher.

Philip Chism is accused in the Oct. 22 death of Colleen Ritzer, a popular teacher at Danvers High School. The 24-year-old Ritzer was found in woods near the school with her throat slit and a note reading, "I hate you all."

Chism's arraignment is scheduled Wednesday in Salem Superior Court. He pleaded not guilty at his earlier arraignment in District Court. The case was moved to Superior Court after he was indicted last month.

Chism had recently moved to Massachusetts from Clarksville, Tenn.

Police have not released a motive for Ritzer's killing.