Allan Cope, head of Tower Hill primary in Farnborough, Hampshire, where Year 5 and 6 pupils are now set for maths and English, describes it quite simply as, "the most effective thing we've done for a long time".
It was his experience as a parent which led him to introduce sets. When his two sons both started secondary school and were set and banded for different subjects, he noticed a rapid improvement in their attitude towards school.
"It was quite clear to me that if they had had the opportunity to work like this before, they would have benefited from it," says Mr Cope.
He is convinced that setting increases the motivation and confidence of even the least able pupils. An elitist attitude which would destroy the self-esteem of those in the "lower" bands will only creep in if a school handles the issues insensitively.
At Tower Hill, children are not categorised through standardised tests; the aim is to place them with other pupils working at a similar level by using a wide range of assessment activities.
The new system was introduced after extensive consultations with parents and governors. Flexibility between bands ensures that children can transfer from one set to another if they need to, but only after discussions with their parents.
"Parents have been enormously supportive because they can see that their children are getting the best," says Mr Cope.
The sense of relief among the staff is palpable. They no longer have to contend with groups mixed both in age and ability; pupil numbers at Tower Hill mean that Years 5 and 6 have to be taught together.
"I'm 100 per cent happy," enthuses Mandy Harrison, the school's deputy head, who is teaching a maths set of 18 less able children, with support from a special needs ancillary. "The children in this group are really growing in confidence because they're no longer frightened of getting things wrong. "
"I like this group better because you get more attention," says nine-year-old Stacy.
The most able pupils are in groups of around 30, but the main benefit for them is a wider variety of work. According to their maths teacher, John Smith, their workrate has increased. He finds it far easier to gear work individually, and can do more whole-class teaching.
Stuart Taylor, who teaches the middle maths group, says that his pupils have blossomed, now they're no longer in the shadow of the more able children. He thinks the children also enjoy a change of teacher, and the chance to work with different pupils.
Mr Cope believes that the new scheme eases the transition to secondary school, as Tower Hill pupils are now used to moving round from class-to-class with the equipment they need for lessons. He is also encouraged by results from his native Nottingham, which suggest that setting improves primary pupils' performance.
But he emphasises that setting at Tower Hill is embedded in an integrated primary curriculum; after maths and English lessons, children return to their mixed-ability classes. He doesn't believe that setting would be appropriate for his younger pupils, and contests the idea that setting should be used as a vehicle for increasing class sizes.