Pupils are given sleep lessons to make sure they stay awake in the classroom

Schoolchildren are being given lessons in how to sleep in an effort to improve their moods and performance in class.

The sessions, run by the charity Sleep Scotland, aim to teach pupils tips such as the importance of a bed-time routine and avoiding late-night television.

Teenagers should be sleeping for more than nine hours a night.

But researchers found that after going to bed at 11pm or later, many then stay awake for hours longer playing computer games, watching television or surfing the internet, leaving them exhausted in the morning.

Experts believe that without sufficient sleep, children's performance at school can suffer, while other issues such as obesity and depression can be exacerbated.

Nikki Cameron, a sleep counsellor working on the project, said: "Sleep for young adults is a hugely significant factor in terms of educational achievement and their physical and mental well-being.

"There is more of a problem now than in the past. Teenagers are naturally programmed to sleep after 10 o'clock, and they're programmed to sleep for nine hours.

"What happens is that their favourite television programme comes on at 11pm, so they'll sit and watch that until midnight, then they may sit and play computer games. One of the things we all do is say 'oh, it's okay, I'll catch up later on, or at the weekend', but that's one of the worst things a child can do, because it disrupts their sleep pattern."

Ms Cameron said addressing the problem has been made harder by a wider social attitude towards getting by on small amounts of sleep, but insisted that ensuring children were getting sufficient sleep was as important as making sure they ate five pieces of fruit and vegetables a day and did regular exercise.

One 15-year-old who has attended the first of a series of sessions said he had tried going to bed early as a result of what he had been taught. "I went to my bed at ten-ish rather than 11, and I do feel a little bit more awake," he said.

"I wasn't sleeping in French, as I usually do, so my French teacher is pleased anyway."

The charity hopes to use the pilot project to develop a course which could then be offered to schools across Scotland.

Sleep Scotland director Jane Ansell said: "You wouldn't send somebody to school without having the right amount of food, so why would you send them without enough sleep?

"We would like to see the government to fund a programme that we can take to schools, and which they can take on board in their curriculum."

A spokesman for Glasgow City Council said: "We are committed to providing guidance to young people so they can get the right amount of sleep and maximise their learning potential."

Top tips for a good night's kip (or you could just count sheep

Get fresh air throughout the day. A 30-minute bike ride helps the body to produce the hormones that aid good sleep later on.

Not having fizzy or caffeinated drinks after 3pm will also have beneficial effects come bedtime.

Avoid watching television or using computers before bed. The light from screens is known to affect melatonin production, a key hormone in preparing to sleep.

Have a regular bedtime and a regular waking-up time. This trains the body to a healthy routine.

Relaxing in the evening is important, as this gives the body the chance to do what it naturally wants to do: rest. Thus, creating a pre-bed routine is important: having baths, winding down etc.