The phrase "a time when children" is correct and usable in written English.
It can be used to refer to a specific period or occasion that involves children, often in a nostalgic or reflective context.
Example: "I often think back to a time when children played outside until sunset, free from the worries of the world."
Alternatives: "an era when children" or "a period when children".
That was also a time when children died for want of food and adults for want of medical care.
'Neville and Beryl had grown up at a time when children, even the poorest, were expected to have hobbies.
At a time when children around the world are returning to school for the new academic year, Syrian children are enduring bombardment, displacement, deprivation and even torture.
Mr. Cohen acknowledged that union officials had discussed the presence of the rats at a time when children were coming into the school.
Lieutenant Roman said that in his 21 years with the department, he did not recall a time when children had been kept indoors because of a bear threat.
"The One Show is broadcast at a time when children are watching - they could have been scared and upset by his aggressive statements.
There was a time when children attending birthday parties received simple favors like a noisemaker or a trinket for winning Pin the Tail on the Donkey.
Halloween is usually a time when children with treat bags slosh through drifts of fallen leaves, and bare limbs and branches are eerily etched against a moonlit sky.
For Ms. Nazmack, it was a time when children started every school day with a prayer to God and "nobody made all this fuss".
At a time when children with the disease died at an average age of 11, Amy lived to be 19 years old, "a joy until the last few months," he said.
In parts of northern Europe, particularly the Low Countries and some German-speaking areas, St. Nicholas Day has remained a time when children are given special cookies, candies, and gifts.
