Open Question: Becoming a Pediatric Oncology Nurse?

I'm a sophomore in high school, and I want to become a Pediatric Oncology Nurse. I want to know what types of classes I should start taking now, and any other types of things I should do to prepare myself. I also want to know how many years of college I would have to have, and what exactly I would need to do in college, and what classes I would take. I live in Canada, if that makes any difference at all.