The Carers Trust and The Children’s Society has found 500 carers in just 35 schools, which equates to 15 young carers per school.

The 2011 Census found that there are more than 166,000 young carers in England, but the charities have called this “the tip of the iceberg”. They have estimated that there could be around 700,000 young carers – one in every 12 schoolchildren – who are unrecognised and go unsupported.

Previous research by the charities found that, on average, young carers miss or cut short 48 school days per year. They also often have lower levels of self-confidence, mental wellbeing and educational attainment at GCSE level.

The 35 schools surveyed are part of the Young Carers in School programme, which is jointly managed by the two charities, and launched last April.

Under the programme, schools can receive guidance and tips on how to support young carers. Regional networks of schools have also been established to share innovations and training.

Mary Bousted, general secretary of the Association of Teachers and Lecturers (ATL) said the findings emphasise the need to support young carers.

“No one can fail to be moved by the situation that our young carers find themselves in,” she said.

“These young people are some of the most vulnerable in our society and are carrying a tremendous burden of care.

“This research highlights the importance of identifying young carers, recognising their complex needs and supporting them to achieve their potential.”