Commenting as the government publish their review into extending the school day, James Bowen, director of policy for school leaders' union NAHT, said:

“There is very little evidence to support a blanket extension of the school day. In fact recent research has shown that the variation in outcomes between schools that have the same length of day are as great as those with different lengths of day.

"Unsurprisingly, it is the quality of education that counts, not the quantity.

"Furthermore, a simplistic approach of just counting hours misses all sorts of subtle differences, such as different lengths of lunchtimes.

"Given that the Secretary of state has been clear that he will be guided by the evidence, it is important we now move on from this unhelpful debate and focus on the things that really do make a difference.”