The right to play is enshrined in the UN Convention on the Rights of the Child
Teachers are being urged to make more time for play during the school day.
Research for Play England suggests nine out of 10 parents think their children work harder in class if they are given time to play in school hours.
And 88% of parents think they behave better in lessons if they can play at break, according to the poll of 2,067 adults and children.
The government said it was down to individual schools and councils to see how break times fit in the school day.
Nearly three-quarters of children say that school is the main chance they have to play with their friends.
Some 55% say they sometimes rush their lunch in order to have time to play with their friends.
And 84% of parents are against play times being shortened.
Play England, which promotes access to free play opportunities, called on schools to protect play time and make more time available for play during the school day.
Director of Play England Adrian Voce said: "The opportunity for children to play at school is all too easily regarded as a luxury. But children, as well as their parents, are telling us how crucial it is.
"We know that playing is an essential part of enjoying childhood and that it contributes hugely to children's informal learning and development.
"Families are now telling us that it is important in helping children to get the most from their formal learning too."
A DCSF spokesman said it was important for children and young people to have the opportunity to play during the school day.
"Break times allow them to meet with friends, 'let off steam' and return to lessons refreshed and ready to concentrate on their lessons. Our recent Schools White Paper makes it clear that schools need to support pupil wellbeing.
"Our Play Strategy set out a range of commitments for how we will work with school capital programmes, for example the record investment through BSF, to improve school grounds and facilities."
The right to play is enshrined in the UN Convention on the Rights of the Child.