But despite detailed criticisms, the borough stops short of calling on the Government to drop the scheme.
Conference papers leaked to the Labour party, which will form the basis of the borough's submission on vouchers to the Commons select committee on education next week, state: "The demands of voucher collection cannot be underestimated, especially for schools. The exercise has taken time and resources. This is difficult to quantify but it has been significant. Publicity and setting up systems to monitor and assist schools have helped a lot. This is a very important lesson for Phase 2. The commitment and professionalism of headteachers and staff in schools have been critical to making Phase 1 work."
As reported in The TES on September 27, Westminster has submitted a damning report on nursery vouchers to the select committee, and the third London borough involved in the voucher pilot, Kensington and Chelsea, has also criticised the scheme.
Wandsworth says the problems have are distributed unevenly among schools, with some having to make great efforts to chase up the vouchers from parents.
The papers say: "For councils who admit three-year-old pupils into nursery classes, the possibility of some parents continuing to be reluctant to apply for a voucher is a very real issue. Where this happens, it is right that continuity of education takes precedence over the technical problems of securing a voucher. A child's place at a school should be guaranteed while the voucher, or, more precisely, the lack of one, is sorted out, although this does, and will continue to add, to the work of schools and local education authorities."
It concludes: "There remains work to be done in continuing to improve publicity and administration, in particular, in explaining the scheme to parents. While Phase 1 has highlighted some problems, it has also demonstrated that those can be overcome."
Margaret Hodge, the Labour party's under-fives inquiry coordinator, said Wandsworth had difficulties with the scheme despite a Pounds 48,980 "sweetener" from the Department for Education and Employment to cover the borough's setting-up costs for the voucher scheme.
Steve Mayner, a Wandsworth education spokesman, said: "It is disingenuous of anyone to think we would produce any whitewash...The whole point of the pilot was to iron out teething problems so that when the voucher scheme goes nationwide, it goes fairly smoothly."
He said it was disheartening that Wandsworth's honest account of the problems had generated "a climate of intellectual fear".
Meanwhile, the council's Labour group has criticised the Government for spending Pounds 1.1 million on publicising vouchers in the four Phase 1 areas of the scheme.
A spokesman said: "With Pounds 360,000, Wandsworth could have provided six new nursery units with places for 450 children. The whole Pounds 1.1m could have provided 17 new nurseries with 680 places in the four pilot areas."