My father was one of those British schoolchildren, he was born here in the US and had dual citizenship until he joined the US Merchant Marine at age 17.
At the outbreak of the war all the kids from Dundee where he lived were sent north of the city with their mothers, my father being the oldest was sent to live in a hotel in Stonehaven, his siblings about a mile away.
My grandfather stayed behind and dug out and built an Anderson bomb shelter for the family and a few more for a few neighbors (one a double amputee from WWI).
The family returned after a few months and used the shelter (knee deep with water) during a few target of opportunity bombings of Dundee.
My father’s family was the only family not to suffer a death from fighting or malnutrition on his street - he said my grandmother’s garden and stretching out the available food by making soups saved them.
My mother in law was one of those children sent to the country also. She was 8. She stayed at a boarding. school. I have the letters that were sent home. Her mother saved them all. It is fascinating to read of her everyday life. The letters span from that time to she was about 20.