But the class is not out of control. Rather, the children are desperately trying to catch Mrs McMullan's eye and be chosen to answer the sum she has written on the blackboard. The number of the day is 54 and every child in the class must come up with a sum that - through addition, subtraction, multiplication or division - ends in 54.
Every lesson at Tudhoe St Charles Roman Catholic primary school, near Durham, begins with a similar 10-minute question-and-answer session led by the teacher from the front.
The warm-up is just one of the changes to maths lessons since the 223-pupil primary joined the numeracy pilot a year ago. Maths is a structured three-part session starting with a warm-up and moving through half an hour of detailed instruction to a five-minute summing up at the close.
No longer does the bell bring an arbitrary ending to a lesson . Instead the 'warm-down' allows teachers and pupils to recap problems - or ideas that have sprung up - and give a clear focus to what they have learned.
Headteacher Tony Kemp admitted: "At first the teachers thought it was horrendous. They said there was no way that our children would be able to achieve these standards because they were so much higher than we were used to. But after a few months they said the pilot was fantastic. The children were amazing with the things they were coming out with and our expectations of them went up dramatically."
Deputy head Elaine Kirkpatrick said: "I was reluctant at first because I had just worked out a teaching programme of my own. But it definitely gives the children more activities to do and they love the mental arithmetic at the beginning of the lesson.
The number of pupils achieving at least level 2 at maths key stage 1 went up from 83 per cent to 93 per cent last summer. At key stage 2 the percentage achieving at least level 4 rose from 52 per cent to 78 per cent. Mr Kemp is reluctant to give too much credit to the pilot which only began a few months before the May tests, but is confident the school will see a big improvement over the next three years.
"We are not going to change the ability or intelligence of children, but we are giving them maths to match their own capabilities and within that level stretching them as far as we can," he said.