I weighed my 13-year-old daughter's school bag this morning. It weighed 12 pounds and she also had to take PE kit.
The main reason is that the old "classroom", where a class stays put and subject teachers come to it, has disappeared, as has the personal desk where books can be kept. There are two main reasons: the need to have "subject classrooms" full of posters and equipment to impress Ofsted inspectors; and the risk of vandalism to books and possessions not kept with the child at all times.
To save children's backs and quash the "school run" major changes are needed in the way schools work - not just new furniture.
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