A.Khan,
I applaud you for your desire to serve in the Canadian Forces. Unfortunately you didn't say where you are located, and this piece of information would have given me some inclination to whether or not to suggest the Co-Op program. The Co-Op program is not accessible to high school students depending on which Province they're located in. For example here in British Columbia, there are no Co-Op programs available for the hs students, however there is a work experience program.
I will expand on the work experience program a little more for those of us in the CF that would like to spear head a trial version with their own units.
The Work Experience Program here in British Columbia is a individual unit effort where High School students are given a period of time (7 days) to experience life as a soldier, with the specific element or regimental taste. units that I know have done this sort of thing previously are 744 Communications Squadron and 15th Field Artillery RCA. Both had success in its enrollment, and its interest.
The students are treated like service members, and are expected to behave in a professional manner at all times. They are taught rudimentary drill, weapons handling, navigation, section tactics and so forth. There were also talks by recruiting staff, and members from other regiments and units.
This maybe something you can look into if you're from BC, or if you're from ON, then try your local school board for Co-Op information.
Hope this helps!