Wet pants at school are embarrassing for the child, upsetting for parents, and inconvenient for the teacher. "Teacher wouldn't let me go to the toilet 'cause it wasn't break" is a familiar cry.
Rosemary Heald, a teacher at Fowlmere county primary school in Cambridgeshire, believes she has a solution to the problem - toilet passes - a regime which has been successfully used at her school for five years.
"I use one pass (laminated card with simple rules printed inside) for girls and one for boys. They live prominently by the classroom door, and may be taken without asking permission. They have to be returned in order for another child to use. The simple rule is, no pass, no go."
She says it means that the teacher is no longer toilet monitor and the number of WC visits has dropped significantly. And the attention-seeking child can no longer use the request as a device.
She adds: "There have been no 'embarrassing incidents' since I switched to this system, and it is even considered to be one of the grown-up privileges anticipated with excitement by children entering key stage 2."