Merton’s primary schools will need to accommodate an extra 450 children per year by 2012, according to a new council report.

The document suggests that expanding existing schools, rather than building entirely new ones, is the council’s preferred strategy for tackling the explosion in pupil numbers.

Parents fear this will lead to overcrowding and the loss of playing fields.

Some schools already have firm plans to increase admission numbers including Holy Trinity Primary.

A proposal to create an extra form of entry containing around 30 pupils at the Wimbledon school went before governors last night.

If accepted, the plan would lead to extensive building work to accommodate a higher number of pupils.

Some parents and local residents have attacked the plan, which they claim would leave the Effra Road school overcrowded.

Oksana Wenger said: “During the build there will be no whole school assemblies and no hot, healthy lunches. Upon completion there will be a much smaller space to play in, no green space to run on and no summer fair.”

Richard Hawtin, the school’s chair of governors, said: "The board of governors has been asked by the London Borough of Merton to consider the expansion of Holy Trinity school to a two-form entry school.

“The board will be meeting later this week to consider the outcome and to give its decision to the local authority concerning whether or not to move to the next stage in the process."

The council report, released earlier this month, said that unexpectedly high birth and school enrolment rates in the borough have caused a dramatic rise in predicted pupil intake for the years ahead.

The report added that while building a new school is a possibility, the council should “ensure that there are plans for up to 12 schools to be expanded” by 2012.

Alongside Holy Trinity, Mitcham’s St Thomas of Canterbury and Benedict schools and Wimbledon Chase Primary are also considering expanding their intake in the next couple of years.

Councillor Krystal Miller, assistant cabinet member for schools, said: “We understand the strength of feeling of those who will be immediately affected if the proposed expansions go ahead, which makes these decisions even more difficult to make.

“We need to ensure we have sufficient places in our schools for all those Merton children who want them.

“While we’re looking at a range of options for places across the borough, Holy Trinity and Wimbledon Chase have a good record of achievement and we would like more local families and children to benefit from the opportunity expansion will provide.”

If the Holy Trinity plan is accepted, it will go forward to a final decision at a council meeting on December 15, when a proposal to permanently expand Wimbledon Chase Primary School to take in a third form of entry will be also be decided.

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