HEAVING bags between classrooms is leading to back problems among secondary pupils, a physiotherapist has warned. Jenny Wigram surveyed 12 to 14-year-olds at South Dartmoor Community College in Devon, and found that half of the 200 who responded had suffered lower back pain in the previous month. Many students complained that the pain was a result of carrying heavy bags, with many schools no longer providing lockers or personal desks.