Craig: Nine years before Rosa Parks refused to surrender her bus seat in Montgomery, Alabama, a beautician from Halifax named Viola Desmond sat down to watch a movie at the Roseland Theatre in New Glasgow, NS. She didn't know she was seated in a whites-only area, and when asked to move to the segregated balcony above, she offered instead to pay the difference in ticket price. Desmond was forcibly removed from the theatre, jailed overnight, convicted without counsel, and fined $26 (about $300 in today's currency). She paid the fine but appealed the verdict, which stood until Desmond was granted a posthumous pardon in 2010. But at the time, the publicity around her case and her bold stand against racial segregation helped advance civil rights in Canada.

Marc: We had never heard of this moment in Canadian history until a friend recommended a kids' book for my daughter, Lily-Rose, called Viola Desmond Won't Be Budged (Groundwood Books, 2010). We knew of Hugh Burnett and the 1950s anti-segregation movement in Dresden, ON, and of Lincoln Alexander, Canada's first black Member of Parliament. But like other cornerstones of Canadian society, the still-unfinished fight for human rights and racial equality has been waged not just by well-known leaders, but by ordinary citizens.

Craig: Viola Desmond's story reminds us that Canada is great because Canadians make it great. From free health care and social programs to our economic prosperity and vast areas of protected natural spaces, there's a lot to celebrate on Canada Day. But July 1 should also be a day to reflect on how each of us can contribute to an even brighter future.

Marc: We're continually inspired by ordinary Canadians doing extraordinary things. One of my mentors, Fintan Kilbride, worked for 55 years with the world's poorest people. He survived a plane crash while delivering medical supplies in Nigeria in 1968, was expelled from Biafra for his aid work in 1970, and started a cooperative education program in Toronto in the 1990s through which students like me could earn school credit for community service overseas.

Craig: One of my greatest heroes is June Callwood, who founded more than 50 Canadian social-action organizations, including youth homes, women's shelters and the AIDS hospice Casey House. I'll never forget the wisdom she shared with me shortly before she passed away. "Changing the world is not a sprint—it's a marathon," she said. We each have innumerable opportunities in our lives to make a difference, no matter what we've done before.

Marc: I get goosebumps when I hear of Canadians like Jessie Jollymore, a dietician in Halifax's north end who launched a youth-led community garden and social enterprise selling homemade salad dressings, despite naysayers telling her the project would be vandalized and a waste of time. She has helped more than 40 troubled youths and their families learn about healthy food and relationships, self-reliance, caring for their community and taking ownership of their futures.

Craig: Or Kennedy Baker, a teenager in Nanaimo, BC, who turned her own tragedy and mental health issues into an opportunity to help others who are misunderstood, vulnerable and in need of compassion. She started volunteering at a local soup kitchen, then began organizing benefit concerts to help feed and clothe hundreds of Vancouver Island's homeless.

Marc: Then there are the four humble Canadian activists who held a teach-in in Saskatoon called "Idle No More," which launched a revolutionary grassroots movement on aboriginal treaty rights and generated a nation-wide conversation on building respectful, cooperative relationships between First Nations, Métis, Inuit and non-aboriginal Canadians.

Craig: Not to mention the countless other Canadians working outside the limelight: the environmental groups cleaning up parks and waterways; the social entrepreneurs providing good jobs, products and services; the teachers and social workers helping kids become confident and capable adults; the scientists toiling away at new discoveries in health and technology; and many others we may never hear about but whose impact is deeply felt by someone.

Marc: Our great country is a work in progress. So whether it's poverty, bullying, gender violence or any other issue, lets each build a better Canada, one action at a time. Like Viola Desmond, we don't have to be a household name, leader of a nationwide movement or even a self-described "activist." We just have to look for a need, injustice or opportunity to make a difference, and have the courage to take action. That, plus a barbecue and a few fireworks, would make this Canada Day complete.

Craig and Marc Keilburger are founders of Free The Children and Me to We.

For more inspiring stories from Craig and Marc Kielburger, check out how young Canadians are changing the world.