Nearly half of Ireland's teens say that peer violence at school affects their studies.
That is just one of the findings contained in a new UNICEF report, which analysed survey responses from more than 3,000 Irish teenagers.
It found that fights and bullying disrupt education for 44% of 13- to 15-year-olds while more than one in four of the same age group were bullied in the past couple of months.
UNICEF Ireland executive director, Peter Power, said: "Education is fundamental in a child's life and every child should feel safe and secure at school.
"Our new report shows that 44% of students in Ireland aged 13 to 15 report either being bullied or being involved in physical fights with their peers.
"This must be addressed - violence is not a lesson any child needs to learn.
"Experiencing violence has serious effects on a child’s well-being, and in the long-term it can lead to depression, anxiety and even suicide.
"No child should go into school fearing violence."
Some 28% of students aged 13 to 15 report they have been bullied at school at least once in the past couple of months - while 27% reported having been involved in a physical fight at least once in the past 12 months.
Across the world, half of students aged 13 to 15 - around 150 million - report having experienced peer-to-peer violence in and around school, according to the 'An Everyday Lesson: #ENDviolence in Schools' report.
The report outlines a variety of ways students face violence in and around the classroom.
According to the latest available data from UNICEF, slightly more than one-in-three students aged 13-15 globally experience bullying, and roughly the same proportion are involved in physical fights.
Three in 10 students in 39 industrialised countries admit to bullying peers.
In 2017, there were 396 documented or verified attacks on schools in the Democratic Republic of the Congo, 26 on schools in South Sudan, 67 attacks in the Syrian Arab Republic and 20 attacks in Yemen.
Nearly 720 million school-aged children live in countries where corporal punishment at school is not fully prohibited.
While girls and boys are equally at risk of bullying, girls are more likely to become victims of psychological forms of bullying - and boys are more at risk of physical violence and threats.
The report also notes that violence involving weapons in schools - such as knives and guns - continues to claim lives.
It says that in an increasingly digital world, bullies are disseminating violent, hurtful and humiliating content with the tap of a key.
The report is based on UNICEF analysis of data from 122 countries with data from the HBSC and GSHS surveys, covering 51% of the global population of children aged 13 to 15 years.
Irish data was sourced through the HBSC survey conducted during 2013 and 2014.