BOYS have more negative attitudes to school and are like-lier to misbehave while girls generally have a more positive attitude and are likely to be praised for their work.
A comprehensive report on children in Ireland has found "messing" is a very common and "normal" part of school life, particularly among boys.
More serious issues such as truancy and being suspended were experienced by only a small number of 13-year-olds.
However, the Growing Up In Ireland report revealed worrying evidence that children from households where nobody was in employment were more than twice as likely to receive detention as those from professional or managerial households.
It also found that around 14pc of children of this age say they have "nowhere" they can go to get information on sex and relationship issues.
Mothers are the likeliest source of information, with 43pc of girls and 20pc of boys seeking their advice.
Only 11pc of boys and virtually no girls report going to their fathers for advice on these issues.
Friends, teachers, the internet, magazines and books or a brother or sister are other sources 13-year-olds go to for information on sex.
The report examines how 13-year-olds and their families are faring across areas including education, physical activity and obesity, family life, finances and relationships.
The results are based on interviews with children and their families, four years on after last being questioned at the age of nine.
In general, 13-year-olds get on "very well" with their parents and get on well at school, though there are differences between boys and girls and children with different economic backgrounds.
The authors of the report expressed concern at their findings that show boys from households with the lowest incomes are twice as likely to misbehave as those with the highest levels of income.
Statistics show 34pc of children from non-employed households had received detention compared with 16pc of 13-year-olds from professional or managerial backgrounds.
Similarly, young people whose mothers had lower levels of education were more likely to have received detention – 28pc compared with 16pc of those with graduate mothers.
Dr Emer Smyth of the Economic and Social Research Institute's (ESRI) education research department said the education system is currently geared towards exams. As a result, more boys are falling into "negative spirals of misbehaviour" as they lose interest.
"That is a concern and is something that can inform policy," said Dr Smyth, explaining that the planned Junior Cycle reform is designed to "avoid the drift away" in second year of secondary school.
The report also found that boys are more likely than girls to exercise, with 30pc of girls overweight or obese in comparison to 23pc of boys.
However, 78pc of children who were obese were exercising to lose weight, showing that they and their parents were making efforts to combat the problem.
A leading youth organisation has welcomed the publication of the report, saying it points to continuing issues around the most disadvantaged in the education system which have been "present for a long time".
Michael McLoughlin of Youth Work Ireland said the findings on self-image were also important, adding that support for informal networks and youth drop-in centres are key elements of the preventative and early warning systems needed to maintain positive self-image.
"We need to assist with resilience locally to deal with the mental health challenges which have become tragically too apparent for young people in recent years," he said.