Young people are afraid to tell teachers about abuse at home because they fear social workers or the police will be called in. Families would then be split up.
Claire Houghton, a children's rights worker with Scottish Women's Aid, said that young people were reluctant to talk to teachers. "We are not getting through to them and supporting the non-abusing parent," Ms Houghton said.
Pupils also worried that teachers might tell others in the staffroom and start school gossip. Other pupils might find out.
One S4 pupil said: "Teachers won't understand and will only interfere and make things worse than they already are."
Another said: "No one wants to get attention for having something wrong with them or their family."
Instead of admitting their difficulties, they tried to pretend that everything was all right, although inevitably they were angry, frightened, lonely and depressed. Feelings of being unloved and unimportant are common.
A recent study among 254 senior pupils in South Ayrshire (TESS, September 17) found that almost one in three had witnessed abuse at home, and the main victim was their mother.
Douglas Hutchison, a South Ayrshire psychologist, said abuse and homelessness went together because many mothers eventually left home with young children. Research in Birmingham showed that women seek refuge after an average of 28 assaults.
Three out of four children in such families had witnessed violence and one in 10 had seen their mother sexually assaulted.
Half of such young people, Mr Hutchison said, developed mental health problems. Pre-school and primary children had short attention spans, were withdrawn or aggressive and suffered from sleep disorders, poor social interaction and clinical disorders.
Studies had shown that children from abused families where the mother had left home to seek refuge were more likely to be involved in street or playground violence and had a much higher incidence of ADHD (attention deficit hyperactivity disorder).
Ms Houghton said that a change of school meant problems. Young people feared being outcasts. They felt they did not have the right clothes and teachers got on at them because they did not know the work.
While such children are reluctant to admit abuse, 94 per cent say they want prevention strategies taught in school.
A national strategy to combat domestic abuse was launched by the Scottish Executive four years ago. It stressed that children are "witness to and subjected to much of the mental, emotional, physical and sexual abuse of their mother".