I was in your place a year ago. I really wanted to be a nurse, but didn't have my bio or chem.. so I went back to school this year and instead of taking just those classes I took a full prep for health sciences year, which also gave me the credits I needed. I had been out of school for 7 years, traveling and having a baby and being a mom, so it got me used to school again.
I am now in for nursing school
in September 07!
If you are planning on school in Canada, you can take either just the courses you need part time, or do a program like I did. However, I suggest you figure out where you want to go to nursing school and then contact that school and ask them exactly what you need. They will be the best help, since different schools
accept (or don't accept) certain programs.