It's likely not on your calendar, but today is National Child Day. In its honour, we introduce four people who aren't waiting for grown-ups to change the world -- they're doing it themselves.

Meet Maddison Babineau, 15, who is coping with her cancer by selling jewellery from eBay to build a well in Kenya.

Her first wish is already becoming reality -- a school for Kenyan kids is being built on her behalf.

Sabrina Pursley, 11, is planning her fifth walkathon to raise money for McMaster Children's Hospital, as a way to thank the staff who took care of her when she wound up there with a kidney infection at age five.

William Pearson, 17, was the guy who came up with the idea of refurbishing broken computers in his Waterdown community, computers now being shipped to a training centre for street boys in Zambia.

Kellie Guzzo, 23, founded Out of the Heat, a summer program to feed hungry folks in Hamilton.

National Child Day marks the United Nations' adoption of the United Nation's Declaration on the Rights of The Child (1959), and the United Nations' Convention on the Rights of the Child (1989). Check out the Canadian Children's Rights Council, www.canadiancrc.com.