Children at The Green Way Primary, in 21st Avenue, have complained to teachers about the grown-ups' language.
Now, pupils are designing their own eye-catching posters in a bid to shame the offenders.
Simon Bush, deputy head teacher of the school, said it was important the problem is tackled swiftly.
He said: "During a school council meeting a Year 6 boy said, 'We are very concerned about the amount of swearing on the playground.'
"I thought he meant other children's language but he was actually talking about the parents."
Mr. Bush stressed it is only a "very small minority" of parents who are guilty of using bad language in earshot of pupils.
However, he said the school is determined to eradicate it.
Mr. Bush said: "It is not a massive problem, but there are some parents who do use inappropriate language while picking up their children..