It is 3pm on a winter's afternoon and most of the 69 pupils of Hillside School are gathered in the hall for their daily assembly. Sue Upson, the headteacher, raises her hand and gradually most hands go up. There are, she says, some big achievements to celebrate and she reaches for a pile of certificates.
First up is "J", in a wheelchair. She has completed three modules of the school's transition challenge: moving forward, feeling good and taking the lead.
"Now," says Sue, as the applause dies down. "`A' is going to walk to get his certificate." The reward is for walking 10 metres and he proudly comes forward on his walking frame.
The next certificate is for a girl who can pull herself up to standing, take a paper towel out of the dispenser, move it around and drop it in the bin. Another boy is called to the front for putting all the correct labels on a picture of a wolf, though he is too shy to show the group his picture. The final two awards are for another wheelchair user for sitting up and lying on the floor and for a pupil who has been really good when he is riding.
Today's song is "If I were a Butterfly" and the last line of each verse is, "I thank you Father for making me me". Some of the children join in enthusiastically. "Who would like to say the prayer today?" asks Sue. Lots of hands go up.
A boy comes forward to say his prayer. "Thank you for riding, thank you for Harry, thank you for Curtis, thank you for David."
"Thank you for everybody," says Sue firmly.
She holds up a sign that means the assembly is finished: the school is full of signs because some pupils understand pictures more easily than words. As she switches on some quiet music, two pupils hold up signs for quiet music (a face with a finger to its lips and a treble clef) and the children are called out in groups to the buses that take them home. Each group has an animal's name (more signs). The session is over in just 10 minutes.
The assembly is a small part of a framework for rewarding achievement that operates in every lesson in Hillside Special School in Sudbury, Suffolk, for children aged between two and 19 with severe learning difficulties. About 20 per cent have profound and multiple learning difficulties. Half also have autism spectrum disorder.
Nearly all children are working towards level 1 of the national curriculum and the world of national tests, exams and league tables that permeates mainstream schools seems far away. Individuals have targets and so does the school, but the rewards are designed to recognise achievements that will never feature in a league table. The school applauds every small step of progress even if it has taken a very long time.
Sue says: "It may take three years for a pupil to take their first steps. Letting go of something to put it in the bin for the first time may be difficult for a child. What might seem a very small step can be a big achievement."
Every classroom wall and many of the corridors are covered with reminders of these small steps. The displays are labelled with the pupils' names and their photographs because some do not recognise their name.
The nursery has pictures celebrating four firsts: making marks with fingers in flour, using a new standing frame, asking to draw a picture and taking off shoes and socks. The pictures are fastened to the walls with Velcro so the children can pull them off. For older teenagers, the wall displays congratulate pupils on not eating out of the bowl during cookery, joining in dance during PE, telling the main points of a story without prompting and making an apple crumble without help.
Sue says: "Displays often don't last long because children touch them and pull them off, but we would rather have them there. If they see a picture of themselves doing something it is motivating. We have lots of scrapbooks showing what they have been doing and they look at them all the time."
Teachers use the rewards that are common in most schools: certificates, smiley faces and stickers, and competition prizes. Older pupils also collect points from week to week once they have learnt about the importance of waiting for a reward. Those who finish their work are allowed to choose an activity from a bag.
Hillside organises the curriculum and rewards to suit each child. "It is personalised. We were personalising learning long before the Government started talking about it," says Sue. So the choosing bags all contain different activities. While many children find applause in assembly motivating, some do not: the self-conscious may simply get a smile from their teacher.
Hillside's way of celebrating pupil achievement works. Sue, who has worked in special schools throughout her career and has been at Hillside for four years, says that what happens at the school is common. But the last Ofsted report shows that the education it offers is far from run-of-the-mill.
Inspectors said their findings supported parents' views that this is "an outstanding school . Pupils are cared for extremely well and make outstanding progress in their personal development."
Inspectors also praise the progress in school work: "Pupils with severe learning difficulties and autistic spectrum disorder achieve exceptionally well."
What does Hillside hope to achieve for its pupils? Sue says: "We want them to feel good about themselves, to feel confident. We want to help them to cope in different situations, to be able to do as much as they can for themselves without support."
COULD THE HILLSIDE APPROACH WORK ANYWHERE?
It makes sense to tailor rewards to individual pupils' needs, and a special school such as Hillside is exactly the environment where the staffpupil ratio could make this possible.
What might be a reward for some (public recognition, for example) might be punishment for another (public humiliation or unwelcome attention).
However, this is time-consuming and would be difficult to carry out in a standard comprehensive.
It is a massive oversimplification to focus on the carrotstick approach, but we respond to praise and punishment on a primitive level. Good behaviour is reinforced by sensations of pleasure when we receive praise.
There are dangers in this approach, but they are not insurmountable. If you praise someone repeatedly, they become used to the praise and it no longer provides the same internal glow.
Praising a pupil for any positive activity, no matter how small, offers similar challenges. A dyslexic child writing a page of perfect syntax should rightly be praised as fantastic, but if it is a small success in line with their ability, the praise should be small. Above all, avoid fake praise - most pupils can see through it and it becomes counter- productive.
Tom Bennett is head of religious studies and philosophy at Raine's Foundation School in Bethnal Green, east London.