"Some people are being called bad names.
"We called the police and they gave them a warning but the kids just came back again."
He said it had been going on for weeks and the children would regularly be wearing their school uniforms.
Te Ngae Mad Butcher owner Todd Hughes said it was time to stop.
"They are intimidating customers.
"There used to be one guy doing it which was all good but now there are up to 20 of them."
He said it was alarming customers who were being pushed into paying for their windows to be washed.
"I've told them to get lost and said I'd ring their schools if they didn't go away."
Rotorua Lakes High School principal Bruce Walker said shop owners should not have to put up with it .
"My advice to the shop owners is phone the police and if they are in our school uniform phone us and we will do our best to identify them."
Rotorua police Inspector Ed Van Den Broek said he would be looking into the complaints.
"If they are being aggressive or stopping the flow of traffic or being a nuisance then we will take action. We will be keeping an eye on the situation."
He said the best thing shop owners could do was to report any aggressive behaviour to the police.
"We will send down a patrol if we get more complaints."
Rotorua District Council regulatory and support services manager Jim Nicklin said they were not breaking any laws by simply washing the windows.
"The bylaw [which prevents window washing at traffic lights] has no application here, it only makes it illegal at intersections."
Email: gary.hamilton-irvine@dailypost.co.nz
