Macgregor, Latham, Mount Rogers and Macquarie schools are part of the trial as the government considers measures to cut speeding near schools and improve signs so drivers realise they're entering a school zone.

ACT chief police officer Rudi Lammers said there had been a serious accident, several minor accidents and a series of "near misses" near schools this year.

The worst case was a male motorist speeding at 102km/h in a 40km/h school zone.

"At that speed, it would have taken the driver 130 metres to stop. If he had hit a child, he would have more than likely killed them. At that speed, he would have hit a child at four times the impact had he been driving at 40km/h," Assistant Commissioner Lammers said.

Police would have a high-visibility presence at every school this year and focus on schools with heavy traffic.

Last week, a 13-year old boy received serious injuries when he was hit by a car outside Kingsford Smith School.

The ACT government has sought community views on reducing speeds from 40km/h to 30km/h near high-risk schools.

Education Minister Joy Burch said she had considered the NSW program of installing flashing lights at schools, but given the suburban sites of Canberra's schools and the all-day hours of the 8am to 4pm zones – rather than simply at school drop-off and pick-up times – it was decided to look at speed limits and signs.

"Dragon's teeth", or white triangular markings that signal a 40km/h school zone, would be painted on roads near the trial schools and other signs would be "simplified and uncluttered" with a message that focused on speed, addressing feedback from motorists who said they didn't always see small signs.