Arvada police say the teen, a student at Ralston Valley High School, was charged with five counts of third-degree harassment, CBS Denver reports.
The charges stem from a so-called "burn book" - like the one featured in the movie Mean Girls. In this case, the alleged bullying youth created postings on Instagram under the user name "anonymous."
The pictures of five Ralston students were likely taken from their Facebook page and uploaded to Instagram. Police say under each picture there was a caption with derogatory or sexual comments, according to CBS Denver.
"We received a report of it almost immediately after it was created,"said Jill McGranahan with the Aravada police. "We were able to track the person who did that through their IP address."
Police warn parents to talk to their children about using Instagram and tell them that even if they post something anonymously, it's still possible to track down them down.