A primary school head teacher has written to parents asking them to stop their children from urinating in the playground.
Kay Church said a "small number of pupils" had been seen relieving themselves on school grounds as their parents picked them up at the end of the day.
Mrs Church, executive head teacher of Hannah More Infant School and Grove Junior School in Nailsea, Somerset, called the behaviour "totally unacceptable".
She included an item about "toilet etiquette" in last week's school newsletter.
"Sadly it has been brought to my attention that at the end of the school day a small number of pupils are allowed by parents to urinate in the school playground," she wrote.
"Clearly this is totally unacceptable behaviour particularly as all pupils and families know where the toilets are in school."
Mrs Church said that there had only been one incident of a child urinating in the playground reported to her by parents.
But she is not the first head to write to parents about etiquette issues.
Kate Chisholm, head teacher of Skerne Park Academy in County Durham, wrote to parents asking them not to wear pyjamas and slippers on the school run.
At another school in Yeovil, Somerset, staff at St Michael's Academy wrote to parents about children arriving at school "dirty and unkempt".