At least three Melrose High School students have been hit by cars near the intersection of Mawson and Athllon drives in the past five years, according to principal George Palavestra. And he said an adult was hit recently.

Mr Palavestra and his parents and citizens association have lobbied to have the speed limit on the road behind their school reduced from 80km/h to 40km/h. He said 300 of his students crossed the road after school to catch buses.

''Territory and Municipal Services says it's a major arterial road and they won't change it,'' he said. According to a TAMS spokesman, of 74 accidents from 2007 to 2011, just two involved children.

''Signalised pedestrian crossings are provided to maximise safe crossing opportunities and ensure minimal conflict between traffic and pedestrians,'' the spokesman said. ''These facilities are well utilised by students and teachers.''

There is also an underpass under Athllon Drive about 300 metres north of Mawson Drive and a path from the school to the Mawson Shopping Centre.

He said a bus from Melrose High School to Tuggeranong interchange had reduced the need for students to use the Athllon Drive bus stop.

Melrose High School students Tegan Mulquiney, 16, April Fliedner, 15, and Nick Fripp, 16, were the good Samaritans when the 11-year-old boy's bicycle collided with a car.

The mother of the Marist Junior School student said it was not the fault of the car driver, who called an ambulance. ''[My son] was really lucky, it could have been awful,'' she said. ''But he was back at school the next day.''