Numerous schools across Wales and England have been forced to close by the heaviest snowfall for years.
Decisions about school closures are taken locally
In some cases children were able to get in but staff who travel from further afield were unable to do so.
Closure decisions are taken locally, so there were no central statistics on how many schools were affected, but reports suggest well over three thousand.
There were about 700 closures in Wales and many more across southern and midland counties of England.
All council-run schools in Birmingham, plus those in Solihull and Dudley, have been closed and Birmingham City Council says all its schools will remain closed on Friday.
Councillor Les Lawrence said the bad weather made things dangerous.
"That causes concern about the state of the pavements as well as the roads, especially in residential roads where most of our schools actually have their entrances.
"I think the safety of the children, the staff and the parents are paramount and you don't want lots of parents driving their children to school and causing considerable congestion around school sites on a day such as today."
In total at least 805 schools closed in Birmingham and the Black Country.
In Essex, 439 schools have been closed because of the snow.
Some 300 schools in Herefordshire and Worcestershire closed for the day and 175 in Gloucestershire.
Nearly 100 schools in Staffordshire and Cheshire were shut, about 230 in Oxfordshire, and in Buckinghamshire it was just over 200.
Other estimates for school closures included 100 in Cambridgeshire and up to 100 in Norfolk and Suffolk. The figure in London is put at more than 100 schools.
Other counties with at least 100 school closures included Kent, Berkshire, Bedfordshire, Hertfordshire, and Northamptonshire.
Reasons given on the Bucks County Council website included:
Others, such as Tingewick Infant School, put it more succinctly, with the single word "Snow".
- Many of the staff live a long distance away from school and would not be able to make it due to a heavy snow.
- Nature of the site makes it impossible to make site safe in such snowy conditions.
- [Pupil referral unit] I have also consulted with local taxi companies who are reluctant to go out for children.
- Heavy snow makes access to Bledlow Ridge too difficult for staff and pupils not living there, so not enough teachers can get to school to open it safely.
- No school buses, and staff unable to get in.
In other cases schools were functioning but were short of pupils.
Dorney School in Maidenhead in the Thames Valley managed to open.
"We are monitoring the situation on an on-going basis," it said.
"The school understands if parents do not wish to attempt the journey, but we are open for those who wish to come."
A spokesman for the Local Government Association said this was acceptable because the primary concern was the safety of the children.
"If parents feel they don't want to compromise that by getting into the car or by walking on ice, that's fine."
Even those children who were in school would be "staring out of the window, itching to throw snowballs", he added.
More than a hundred schools used a text messaging system to alert families to closures.
Others employed a more traditional "pyramid" system - one person telephoning a number of others who in turn pass on the message, using a pre-arranged list.
Some simply rely on websites and local radio alerts.
But there were parents who felt schools had over-reacted, when they delivered their children as normal only to find the premises shut.
Childcare services website Emergencychildcare.co.uk has reported record demand for childminders as parents were forced to choose between staying at home to look after their children and finding someone else to care for them.
Ben Black, the website's founder, said: "Many parents are worried that their bosses will think they are making excuses if everyone else has made it into the office."