By Jane Elliott
Health reporter, BBC News
Ceri Symond's back problems started at the same time she started senior school.
Ceri needed regular physiotherapy
Carrying too many heavy books around with her each day for lessons started to take their toll on her growing spine.
Her back would seize up, her muscles become very stiff and she would find it too painful to move.
"It just got worse and worse. It would seize up and it started to hurt when I sat down."
She needed regular physiotherapy sessions to keep her mobile.
Statistics show that half of all children, like Ceri, have back problems at some time and that in 8% of cases it is serious enough to affect their attendance at school.
Even more worryingly, one child in every class will experience chronic disability as a result of their problems.
Experts say many of the problems could be avoided by using better suited bags, doing more exercise and improving posture.
However Ceri, 13, of Camberley in Surrey, says that despite the publicity many children are still oblivious that they are at risk, wrongly assuming that back problems are only for adults.
"I don't think children are back aware.
"I had no idea. Our school, Kings International College, has been trying to raise awareness and we are trying to improve our posture.
"We are even trying to raise enough money to buy some lockers so we don't have to carry all our books around."
Wear appropriate bag over both shoulders
Use lockers, if you have one, to store books
Do at least an hour of physical activity
Try seat wedges to improve posture
Better education in schools about back care
Steve Dinnie, director of sport and health at South Dartmoor Community College, Ashburton, Devon (a specialist sports college for 11-18 year olds), explained that his school has been making back-care a top priority for their pupils.
Assemblies have focused on the importance of suitable bags, new furniture is more ergonomic and the school has a physiotherapist holding weekly sessions on site.
Because few schools have lockers, equipment must be carried
He said: "We give them help on how they can prevent back problems.
"We give them advice on eating healthily and how they should load up their school bags.
"We tell them just to carry around the kit they need for the day and not for the whole week.
"Many of them were not wearing their bags properly they either had single strap bags or they had their double straps attached too loosely, or off one shoulder.
"We would also like to have lockers at the school, but the problem is where we would site them."
Jenny Wigram, a physiotherapist who holds weekly sessions at the school, said she had been deeply concerned about children's backs for some time.
She said pupils not only carried bags that were too heavy and poorly designed, but they also spent long periods sitting at unsuitable desks and hunched over computers on "horrible plastic stacker chairs".
She said she feared that, as technology advances, the problems will become worse - particularly as children get access to hand-held computers which would mean them not having to use their desks for long periods.
Children's spines can be affected by carrying heavy bags
"I think it is a problem of lifestyle.
"Children have a very sedentary lifestyle.
"They also have no lockers and all have to carry their bags around with them.
"They do not always have ergonomically designed bags, as they do not necessarily think they are cool."
She said about one in four of the pupils referred to her clinics have low back pain.
"And this figure does not include mid-back and neck problems.
"It is impossible to categorise their spinal problems into sports injuries versus postural problems.
"The students usually present with a mixture of both.
"Typically they may describe a sports injury which is not the primary cause of the problem but rather the 'last straw'.
"There is usually a background of other causative factors such as school furniture, school bags and lifestyle."
But she said schools like South Dartmoor Community College are now starting to take notice and that when they redesigned their library recently they ensured the furniture was more suitable.
A spokeswoman for the charity BackCare said it wanted to see action taken to help children.
"We are currently lobbying for the introduction of ergonomic school furniture and for schools to meet the statutory requirements to provide storage for pupils belongings.
"We also want back health and posture education to be included in the school curriculum."