Half of teachers have seen an increase in youngsters dealing with difficulties such as anxiety and depression, the surevey says It reveals that half of teachers have seen an increase in youngsters dealing with difficulties such as anxiety, depression, ADHD, hyperactivity, eating disorders, substance misuse and self-harm than they did two years ago, while around 60% have seen a rise compared with five or ten years ago. The survey, conducted by the Association of Teachers and Lecturers , suggests that just over two fifths of those questioned say that between 10% and 25% of pupils in their school or college have mental health issues.