The national schools commissioner is offering schools the option to join academy trusts as “associate members” so they do not relinquish their legal independence.

Sir David Carter said that he would be making the point more widely in future, as a response to hurdles some schools face in joining academy trusts, at a training event held by the Church of England yesterday.

Associate membership allows a school to join a trust in a more flexible arrangement, accessing shared resources and leadership, but it does not legally transfer into the trust.

In some cases the school will pay into the trust’s central funds via a “top-slicing” arrangement, where a fee is taken for each pupil in the school. However in other cases the membership may be free, especially where the school is able to offer training support to others in the trust.

In both instances, the school retains the right to leave the academy trust if the arrangement is unsatisfactory.

“The arrangement could last for something like two years, on the basis that once the time is up school and trust leaders will know if it is the right thing for them and are likely to sign up,” he said.

He believes the change is a positive way forward for small schools which otherwise might struggle to be taken into trusts, or which fear they might be closed after formally signing over all their powers. It also helps church schools wishing to work with a local non-religious academy trust in a way that enables their original ethos to stay intact while still drawing on resources for school improvement.

“A partnership gets around some of the ideology problems, but it helps people improve,” he added.

It is also a way of encouraging governors to allow headteachers to work with a local academy trust without having to give up their powers.

The policy marks a shift in views over flexible arrangements for academies. One of the first types of academy chain, umbrella trusts, enabled schools to retain their own legal status but pay into a central trust which helped with shared resources. The arrangement was gradually phased out in favour of multi-academy trusts, which required schools to give up their individual legal status and became part of one central organisation.

However, a more cautious approach to joining trusts was still needed, especially where schools had complicated financial arrangements. In response, a “try-before-you-buy” scheme developed last year, allowing academy trusts to sign schools up for one year using “a service-level agreement”.

Steve Taylor, the executive head at Robin Hood Academy Trust, which has used the scheme, said one-year deals provided stability while schools sounded out a formal partnership with a trust.

“It provides a transparent way of working that allows the impact of what has been done to be measured before a commitment is made,” he said.

Carter’s new plan looks to extend this option further, as commissioners shift away from worrying about “structures” to a focus on “school improvement”, but it does not replace the multi-academy trust model and would likely only be allowed for short periods.

“It is about allowing good schools, or small schools, to dip their toe into the water and see if it works for them on the basis that they will become academies in the future,” he said.