Ten students were arrested after the fight last week, which took place off school grounds after classes ended for the year.
The video recently posted on YouTube shows the fight involving more than 300 students that spilled into the streets of west suburban Maywood.
The brawls happened on Friday, May 31- the last day of school at Proviso East High School and began around 9:30 that morning reportedly starting in the school's parking lot.
The fights were recorded on cell phones by students and also posted on Facebook.
Police arrested nearly a dozen students including a girl wielding a knife, who alledgely had been previously beaten by other students.
It took the more than 40 officers summoned from neighboring towns and the Sheriff's police several hours to clear the melee.