Education bosses have banned children from leaving Holyrood Secondary at the break after two incidents, one of which left seven children injured.
And police have been drafted in to guard the school gates following an alleged attack on a schoolboy.
As revealed by the Evening Times, the teenager was allegedly assaulted near the school on Monday afternoon. It is now also claimed that six other pupils were also injured at the same time.
Today police confirmed three pupils have been reported to the procurator fiscal and children's reporter in connection with the incident.
The strict lunchtime policy comes just days after angry parents demanded answers when intruders walked into Glasgow's largest school.
The parents told how they were sent texts telling them an "emer-gency action plan" had now been put in place.
Glasgow City Council said officials were looking into a "number of short-term options" to keep pupils at the Govanhill school safe.
A spokeswoman said: "It is a minority of youths who are causing these issues and we will do all that we can to safeguard our young people.
"This type of behaviour will not be tolerated. The school is working with the police to get to the bottom of this matter.
"A letter to parents will be sent home to reassure them that the school is looking at a number of short-term options to safe guard the young people."
Education bosses said a letter was sent out to parents yesterday.
An investigation was launched into the incident at the school on Wednesday last week, when three youths entered the school as more than 2000 pupils studied in their classrooms.
Concerned parents told how they would be walking their children to and from school after last week's incident.
One said: "It's getting worse at Holyrood.
"First there are intruders in the school, then someone is getting attacked.
"Some people had heard that a pupil had been stabbed - we were frantic."
Around 130 teachers are based at the city school.
SNP councillor Mhairi Hunter told the Evening Times: "I will be asking questions of both the education department and the school. This is obviously extremely worrying.
"Parents expect their children to be safe in class."