A 16-year-old is charged as an adult with attempted murder for stabbing a classmate at Coatesville Area Senior High School, according to the Chester County district attorney.Oddell Cannon, of Coatesville, is being held at the Chester County Youth Center on $750,000 bail.Police said the victim, 16-year-old Mickey Rayner, was stabbed repeatedly Tuesday morning. He is recovering at a hospital.According to a criminal complaint, a witness told investigators Rayner believed Cannon had stolen a vape cigarette cartridge from him and wanted to fight.The two met in a bathroom and started to fight, police said. Another witness told police he saw Rayner bleeding and heard him say, "Bro, he stabbed me."Police said a video of the fight was posted on social media, and Cannon is seen stabbing the victim multiple times with an item held in his right hand.