I was back teaching after an absence of 15 years, dealing with the various kinds of "forbidden fruit" that come out of book bags.

Just from the weight and size of school bags, many people believe they were happier as a child than the children are today.

On average, a primary school pupil's school bag weighs 4.2 kg, 53.8 per cent heavier than the recommended weight - which is 10 per cent of a pupil's weight.