New Department for Education guidance stating that schools should not shorten their days or weeks unless it benefits pupils’ education has been criticised as “disingenuous”.

The guidance says that the “structure of the school day and school week should not be the cause of inconvenience to parents” and that it is “unacceptable for schools to shorten their school day or school week unless it is a direct action to support and enhance their pupils’ education”.

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However, the joint general secretary of the NEU Mary Bousted said the guidance was “disingenuous” and that the DfE was “ignoring reality” in failing to address funding cuts that lead schools to reduce their weeks.

“Schools are not doing this because they think it is in the best interests of the children, it’s through lack of funding”, she said.

“They know this inconveniences parents - they aren’t choosing to do this, it’s out of desperation.”

Dr Bousted said schools shortened their days or weeks out of necessity rather than because of a choice “based on sound educational principles”.

“They are telling schools to be virtuous without giving them the means to be virtuous. Schools are facing an impossible choice.”

Dr Bousted pointed out that headteachers cannot run schools on a budget deficit, and said that were they to do so, they would face penalties or possible conversion of their school into an academy.

She said any reductions to school days or weeks would “disproportionately” impact the most disadvantaged pupils.

And she added that the DfE knew the reasons why schools made this choice but were deliberately ignoring them in publishing “disingenuous” guidance.

The guidance states that schools must “organise the school day and school week in the best interest of their pupil cohort, to provide them with a full-time education suitable to their age, aptitude and ability”.

It says that if schools make changes to their days or weeks, they must give parents notice of this, as well as considering the implications for pupils, teachers, parents’ work commitments and childcare.

The guidance says that shorter days or weeks could affect parents’ choice of schools. “When applying for a school place, parents may be more likely to choose a school with a traditional, full-time school week and to appeal against the offer of a place at a school with a shorter school week.

“Schools should also consider the potential impact of a shorter school week on parental choice as part of admissions and admission appeals processes,” the guidance adds.