Students practise for cycling skill for the Bike to School Week at a secondary school in Vancouver, Canada, May 22, 2013. Over 40 schools from Metro Vancouver will participate in the annual Bike to School Week competition. The event aimed to educate the students to support cycling for better health, cleaner air and strong school communities. (Xinhua/Liang Sen) 

Students practise for cycling skill for the Bike to School Week at a secondary school in Vancouver, Canada, May 22, 2013. Over 40 schools from Metro Vancouver will participate in the annual Bike to School Week competition. The event aimed to educate the students to support cycling for better health, cleaner air and strong school communities. (Xinhua/Liang Sen) 

Students participate in a bike training session for the Bike to School Week at a secondary school in Vancouver, Canada, May 22, 2013. Over 40 schools from Metro Vancouver will participate in the annual Bike to School Week competition. The event aimed to educate the students to support cycling for better health, cleaner air and strong school communities. (Xinhua/Liang Sen) 

Students attend a bike training session for the Bike to School Week at a secondary school in Vancouver, Canada, May 22, 2013. Over 40 schools from Metro Vancouver will participate in the annual Bike to School Week competition. The event aimed to educate the students to support cycling for better health, cleaner air and strong school communities. (Xinhua/Liang Sen)