An infant school has employed someone to change nappies because so many pupils are not toilet-trained, a councillor has said.
Chris Towe, Walsall Council's portfolio holder for education, said: "We are talking about five-year-olds here and it is not acceptable."
He said it was among many examples of children in the West Midlands borough starting school without basic skills.
Schools told him many pupils could not communicate or hold a pencil properly.
'Cannot go on'
Head teachers had also raised concerns that school starters could not use cutlery or dress themselves.
Mr Towe told the BBC he had spoken to the heads of 80 infant and primary schools and found the lack of basic skills to be a "massive issue".
"I was quite shocked really," he said. "If they haven't got basic skills, how can they be educated?
"This cannot go on. If it doesn't stop it is going to get even worse."
Mr Towe told a meeting of the Conservative-run council that head teachers believed many children were two or three years behind where they should be, the LDRS reported.
'Not a priority'
"Clearly, over the years, many parents have not been taking responsibility in making sure their children are ready for school," he said.
The council plans to send letters informing parents of the skills children need and where they can get help.
Diane Coughlan, a Labour councillor, said the borough had a lot of vulnerable families with a range of issues.
She said: "For many parents, school readiness is simply not a priority for them, so apart from simply sending a letter what other support will they be given?"
A survey of 700 education staff in 2016 suggested the number of children starting school in nappies had risen.
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