Canadian kids have once again earned an F for "active play and leisure" on a report card evaluating their physical activity levels.

The 2012 Active Healthy Kids Canada Report Card on Physical Activity for Children and Youth finds that Canadian kids are spending a pitiful amount of time playing, with 46 per cent of kids taking part in three hours of active play every week or less.

Out of the four hours or so of free time that kids typically have after school and during their lunch breaks, kids are getting only 24 minutes of moderate- to vigorous-intensity physical activity.

While active play was once a regular part of a child's day, kids are now spending the majority (63 per cent) of their free time after school and on weekends sedentary.

The report card was released Tuesday by Active Healthy Kids Canada and its partners, ParticipACTION and the Children's Hospital of Eastern Ontario Research Institute – Healthy Active Living and Obesity Research Group (HALO).

Dr. Mark Tremblay, the chief scientific officer of Active Healthy Kids Canada and director of HALO, says the amount of time that kids are spending in "unstructured play" is declining with each generation. And that's hurting the health of our children and youth.

"Kids of all ages should have regular opportunities for active play, where they can let loose, explore, run, climb, crawl and play in parks with friends, like their parents once did," he said in a news release.

"Active play is fun, but it is also shown to improve a child's motor function, creativity, decision-making, problem-solving and social skills."

There are a number of reasons kids aren't as active today as they should be, but a big one is parental concerns about safety.

Fifty-eight per cent of Canadian parents say they are very concerned about keeping their children safe and feel they have to be over-protective of them.

Safety concerns, such as crime, traffic, neighbourhood dangers such as bullies, and a lack of supervision, discourage parents from letting their children and youth play outdoors.

So instead of playing outside, many kids are instead spending their time in front of screens.

The report found that Canadian kids are spending seven hours and 48 minutes per day in front of screens -- well above the guideline of no more than two hours per day.

That's despite research that says 92 per cent of Canadian kids would choose playing with friends over watching TV if they had the opportunity.

"We have a responsibility to get out of our children's way and give them the time, space and freedom to run around, direct their own activities and learn from their mistakes," Kelly Murumets, President and CEO, ParticipACTION says all Canadians said in a statement.

"The reward will be increased confidence, a sense of adventure and, perhaps most importantly, a love for being active."

The report urges parents and caregivers to encourage children to choose active play, especially outdoors. To address safety concerns, the report urges parents and caregivers to take turns supervising and playing with children outdoors or encourage kids to play with a buddy.

For the fourth year in a row, the Report Card also assigns an "F" for Screen-Based Sedentary Behaviour, noting that most Canadian children and youth are exceeding the recommended guideline of no more than two hours a day.

And, for the sixth year in a row, the Report Card also assigns an "F" to Physical Activity Levels. That's because only seven per cent of Canadian children and youth meet the Canadian Physical Activity Guidelines of at least 60 minutes of daily moderate-to vigorous-intensity physical activity.

Girls are still trailing the boys in this area: 28 per cent of 10- to 16-year-old boys in Canada reported accumulating at least 60 minutes of moderate-to vigorous-intensity physical activity a day compared to only 17 per cent of girls.