Independent schools have condemned plans to require them to hand over data on five-year-olds’ achievements.

The proposals threaten to widen the rift between the Government and the independent sector over the early years foundation stage (EYFS) curriculum, which was made compulsory for all schools from September 1, 2008.

Currently, while all of those working with under fives are expected to meet the requirements of the EYFS, local authorities are restricted in what they can ask from those schools that do not receive state funding for three and four-year-olds. The data they can demand is set to expand following the publication of a new consultation document this week.

Diana Watkins, chair of the Independent Association of Prep Schools and head of Leaden Hall School, Salisbury, said that while some schools may be happy to work with local authorities, they do not want compulsion.

She said: “There is a huge feeling in the independent sector that this is the thin end of the wedge. Some people choose not to take the funding so they can maintain their independence.”

The foundation stage profile is perhaps the most controversial part of recent changes in early years. To fill in the profile, teachers must assess how children rate on 13 nine-point scales, including linking sounds and letters and creativity.

Currently local authorities can require independent schools, regardless of funding, to provide the total number of points each child has achieved in each of the scales, but this power is not being used. However, local authorities cannot request information about children, such as gender, which would allow them to analyse this information.

The consultation document states: “Given that the EYFS profile is required to be completed at the end of the foundation stage, in almost all cases profile data will be completed by reception class teachers in maintained schools or equivalent classes in independent schools. Such independent schools may not currently be submitting information about children if they do not have any funded children, so this would be a new requirement for these schools.”

The Government argues that local authorities have a duty to improve outcomes for all children and so they need data on all children.

The aim is to allow the extra data collection from June 2009. The consultation closes on May 8.