Stress associated with studies and school is driving droves of teenagers to smoke and drink.
The study carried out by Pamela Taylor, psychologist at Salford Local Authority, looked at the stressors and coping strategies of 172 children aged 15 and 16 years facing their GCSE examinations.
"Teenagers face many pressures at school - continuous achievement, examinations and having to make important decisions about their futures," she said.
The findings indicate that the main stressors for pupils were the volume of coursework they were assigned, clashes with deadlines and teacher-pupil relationships.
Although the majority of the study group listened to music, watched TV, played sport and exercised or walked the dog to cope with stress, some of them confessed taking alcohol and drugs, smoking etc.
Thirty percent drank alcohol to relieve stress, 16 percent smoked cigarettes and six percent used drugs, said a release of the British Psychological Society.
"Over a quarter of these pupils reported suffering from high levels of school related stress. Our results illustrate how important it is to educate teenagers on the best ways to manage this stress, and highlight the dangers of using cigarettes, alcohol and drugs to cope," said Taylor.
"The study also shows there is a need for secondary schools to tackle pupils' school based problems and stressors, including time management, work-life balance and teacher/pupil relationships."
These findings were presented at the British Psychological Society Division of Educational and Child Psychology's annual conference.