There have been few more emotive subjects over the past year than school admissions, as competition for Jewish school places grows.

JCoSS, in Barnet and Yavneh College in Hertfordshire are proposing to do away with feeder schools, which have given children at those schools preference when it comes to secondary selection. While some prospective parents think the change would be fairer, others are far from happy.

And what has angered some of the opponents of the Yavneh change is the possibility that some places could in the future go to non-Jewish pupils ahead of children who have attended a Jewish primary. If that seems odd, then this is how it might come to pass.

Next September, Yavneh opens its primary school - a long-awaited move given the shortage of Jewish primary places in an area of rapid Jewish population growth. Yavneh had been unable to secure backing from the local authority for a new school, so instead went down the free school route, winning approval directly from the government.

However, there is one critical difference between free schools and voluntary-aided faith schools under local authority control: admissions. A religious free school can reserve only half its places for children of its own faith; it has to use other criteria, such as living close to the school, for the rest.

Those who enter on non-faith criteria can still be members of the same faith. So a Jewish free school may be wholly Jewish in make-up, with half chosen according to their faith and the other half because they live near the school.

But there is no guarantee of this. Indeed, Yavneh primary seems to anticipate accepting some non-Jewish pupils. Papers circulated at an open evening talk of an alternative religious curriculum for pupils "not of the Jewish faith".

So how could this affect Yavneh College? One of the proposed entry changes is to give priority not only to siblings of pupils at the college but also in future to siblings of pupils at the new primary school.

Yavneh College is still entitled to give priority to children who pass a Jewish practice test - and it has been heavily oversubscribed since its foundation. One of the ways to obtain a qualifying Certificate of Religious Practice for entry is to attend synagogue a few times a year in the year before.

Not only is there no requirement to be a synagogue member to attend synagogue, but you do not even have to be Jewish. So if the non-Jewish sibling of a pupil at Yavneh Primary wants to apply to the college, all they would have to do is show up at shul a few times and they would be on the priority list for Yavneh College.

Only recently, the Sunday Times's top comprehensives in England were Jewish state schools, including Yavneh. Some non-Jewish parents might be perfectly happy for their children to do a bit of Hebrew if they can benefit from the academic excellence of a Jewish school.

Not surprisingly, this scenario is unlikely to go down well with parents of Yavneh's current Jewish feeder schools.

Listen to our education special podcast looking at the current admissions situation at Jewish schools