Mesnelea primary is losing out because every day more than 20 parents make sandwiches for their children rather than claim the free meals to which they are entitled. Hence, they are not included in the figures which help determine how much money the school is given. Many of those not claiming are single parents, who prefer their children to open a lunchbox with their classmates than have the stigma - as they see it - of receiving a free meal.
Last week the Government ran into major trouble by slashing benefits to lone-parent families. The TES asked three teachers how the cuts will affect their pupils.
* Lesley Auger, aged 48, is a full-time support teacher at Mesnelea primary, in Salford, a school which draws pupils from professional families and a large council estate.
"More important than what money can buy is the effect single-parent family life can have on children. If they are in care before and after school it can be a long day for them. Children are sometimes nodding off at the end of the day because they had to get up early.
"And single parents who go out to work may then have things to do - such as housework - when that time could be spent with their children. It's not the fault of the parent, because it is an awful trap for them, but that is when children are perhaps missing out."
* John Broom, 27, teaches history at Royston comprehensive, a 620-pupil school outside Barnsley in an area of high unemployment.
"The fact that a child is from a single-parent family is something that has an impact outside, rather than inside, the classroom. In the classroom, it is not an issue because all children have equal access to my time and to materials. But I can see it does have an effect on the time, support and attention a single parent can give.
"Teenage girls are asked to do a lot of shopping and to pick up younger brothers and sisters, which gives them less time and motivation to do their homework. It can also affect whether a single parent can find Pounds 4 or Pounds 5 to send their child on an educational visit."
* Ann Morris, 44, teaches a Year 6 class at Valley junior school in Whitehaven, on the Cumbrian coast. The school is on an estate with high unemployment, and around 30 per cent of her pupils are from single-parent families.
"We have a lot of single-parent families who are struggling, often because the parent has a low-paid part-time job which they are trying to fit in around the needs of their children. Most would work more if they had the back-up of proper childcare they could afford.
"The Government's plan for childcare clubs goes some way to meeting their needs, but it needs to look at what can be done in the mornings and school holidays as well. Our single-parent families have a lot of dignity and pride and want the best for their children, so when I get a new class of children I don't instantly pick out which ones are from single families."