Nicola Shipman is executive head of Monteney Primary and Fox Hill Primary in the Yewlands soft federation of schools in Sheffield. She is helped by Morag Somerville, a “superbursar”, who takes on any onerous tasks that might distract Ms Shipman from her focus as head.

Ms Somerville’s tasks include finance and budgets, overseeing building work, preparing reports for governors, health and safety, and recruitment admin.

She said: “It’s important for the head to know about all this, but they don’t have to actually do the tasks.”

She is mainly based at Monteney, but spends two days a week helping the whole family of schools.

Ms Shipman said: “I have far more time to focus on the strategic direction of the school and developing my staff. I also have more time to sit back and reflect. My hours haven’t changed but it’s more about increased capacity.”

Steve Munby, chief executive of the National College for School Leadership, recently said it was “no longer tenable or sustainable” for every small primary to have its own head. His comments reflect a growing view that the burden of bureaucracy and school improvement policy, coupled with a heavy teaching load, is now becoming too much for just one person.

At this year’s NCSL conference, he called on schools to deal with the problem by working in clusters and federations, employing executive heads and “superbursars” - like Ms Somerville - who can take on the business and financial aspects of management over several schools.