The former Olympic swimming coach believes a tough new competency test for Canberra students, issued to schools this week, could be counter-productive.

In order to swim, students will be tested to see if they can enter the pool, walk five metres, swim 25 metres, call for help while floating or treading water for one minute, exit the pool unassisted and perform a voice rescue of another buddy.

Students who pass the exam will then wear a blue tag and require 20:1 teacher supervision and those who don't will be given a yellow tag and require 10:1 supervision.

"The system is going mad," he said.

"Surely common sense has got to prevail. You shouldn't need legislation to take kids to swim. You can't put kids in cotton wool forever."

Ten schools have already cancelled end-of-year fun days, which Lawrence said were important for building children's confidence.

"Its really to the detriment of the kids from enjoying the water. Kid's don't just learn to swim from formal lessons, many learn from exploration, just as they do when they learn to walk or ride a bike," Lawrence said.

His concern echoes that of the Royal Life Saving Society, which has called for the ACT Government to reconsider its policy.

Mr Lawrence said schools should ask parents to assist them on swimming carnivals and fun days, keep students in shallow water while they are learning and just be extra careful.

But he said that parents have got to take the responsibility to teach their kids to swim.

"Parents have to realise that summer is here. This is the most dangerous time for kids and lets see if we can get through this summer with no preschool aged deaths."

He recommends parents should take their kids to classes twice a week and then to the pool to explore and practice swimming in shallow water.