Devonport Schools are warning children to walk in groups after a man with a van has been approaching children inappropriately.
Belmont Intermediate School principal Nick Hill said after two cases where his pupils were approached by the man he sent notices out to parents, contacted the other schools in the area, and filed reports with the police.
A nearby primary school told him a similar incident had happened at their school also.
The man is described as in his 30s, with a white Toyota seven-seater van.
"We've had three children in the space of a week approached by a male in a Toyota van, he's [got out of] the van once, but also followed one of our children along the road in close proximity," Mr Hill said.
A girl was approached by the man before school on Tuesday, then on Thursday a girl was approached by him as she walked home from school.
The man had pulled his car up behind them on the street, got out of his car and came toward one of them, and followed the other down the street.
The girls were both Year Eight and each was walking alone. They said they felt the man was acting threateningly, and ran away from him before calling their mothers who came and collected them.
Mr Hill said the primary school he spoke with about the man said he was seen near children on the school playing courts on Friday morning (5 April), but left before he was asked to.
"Our children need to walk to and from school in pairs or larger groups, at the moment, and they need to make sure they're going home on the most direct route, and they take the same route to and from school - just to be safe," Mr Hill said.
The school would keep reinforcing safety messages to children at school, but it was "very important" parents talk to children about keeping safe, Mr Hill said.
"Don't get into a car, have your cell phone with you, and if you are in trouble go into the nearest shop and ring police."
Mr Hill filled out an online report with police and emailed the local community constable about the man, but had not had replies.
"I've respectfully asked them to have more of a presence in our community, both outside our gates, and in their cars through our community.
"Because my view is that three instances with the same physical description and the same car in a week is really concerning for all of us."
Police did not comment when asked if they were aware of the incidents, or if they would increase their presence in the area.