Linda Yonke, superintendent at New Trier High School in Winnetka, Ill., notified parents Friday via email that the school district had referred to police allegations of students sending inappropriate material by text message, the Chicago Tribune reported. She said the district is conducting its own investigation.
Police would release no details about the investigation.
"Out of respect for student privacy and due to the ongoing police investigation, we cannot share any other details at this time," Yonke said. "All of the parents of students interviewed by New Trier staff have been contacted and informed about the issue."
Winnetka is 16 miles from Chicago on the North Shore. New Trier has long been known for its academic excellence and high per-capita spending.