High school teacher Joan Naydich was violently attacked by Brendan Depa, then 17, in February 2023.
CCTV captures the autistic teen punching and kicking the tutor in the back and head as she lays on the ground unconscious.
Eventually the 6-foot-6 teen, now 18, was pulled away and restrained by other staff.
Depa, who reportedly threatened to kill Ms Naydich during his arrest, was charged as an adult and faces up to 30 years in prison for the first-degree felony charge of aggravated battery.
The teenager was initially charged as a juvenile before being upgraded to an adult.