Why does snow close so many schools?

Hundreds of schools across England and Wales have closed due to snowy weather.

More than 400 schools are shut in Wales. And in Birmingham, the city council has closed all of the schools it runs.

Hundreds more have closed in counties across huge swathes of central England as snow continues to fall.

The short answer is no. There has not been any change in the rules governing school closures.

The guidelines from the education departments in England and Wales are clear. They stress schools can close only in truly exceptional circumstances, when there is no other option.

This is because schools have to be open a set number of days a year.

However, there are no systematic central records held on how many school days are lost to poor weather each year.

Head teachers must make the decision, as they know their school and the surrounding area.

They should use common sense in assessing the risks and aim to keep the school open whenever it is safe to do so, the Department for Education guidelines say.

In exceptional circumstances, a local authority can order a blanket closure of all community and voluntary-controlled schools, but this would not cover foundation or voluntary-aided schools or academies, which are more autonomous.

Child welfare - this includes a number of considerations but focuses on whether:

Staff often travel further to and from school than pupils, so sometimes the head teacher is having to look at transport and travel conditions in a much wider area than parents might imagine.

If the forecast is due to get much worse later on in the day, that can be a reason for closure too.

Health and safety is given a high priority in law so potentially hazardous conditions such as a playground that has turned into an ice-rink or insufficient heating can also be a factor.

Schools without enough teachers will sometimes partially open.

Schools must have in place an agreed communication method for informing parents, guardians, school staff, school authorities and the Department of Education about any closures.

Parents have to be given enough notice to make alternative arrangements for the care of their children, but this obviously varies from family to family.

They should go ahead wherever possible.

If a head teacher decides to close a school when exams are scheduled, they will need to discuss alternative arrangements - such as using other nearby public buildings - with the relevant awarding organisation.

Any contingency plans for exams that have been disrupted will be discussed and arranged with the awarding organisation.

This may involve using evidence of a candidate's likely achievement, or providing the opportunity to sit any missed exam later in the year.