Western Engineering Summer Academy
LEAP at McMaster
Helix Summer Science Institute at York University
University of Toronto has the following: http://www.artsci.utoronto.ca/futurestudents/academics/hsprograms/other
Ryerson paid summer institute program Ryerson.ca/fears/rope - deadline to apply April 1
Ontario Science Centre science school for a semester of grade 12
Ecology Project International Travel and Study program
Here's a collection put together by HWDSB. http://schools.hwdsb.on.ca/delta/student-services-guidance/enrichment-and-leadership/
Here's a collection of enrichment opportunities from the government. I actually was involved in the last one (Youth Challenge International) and did development work in Costa Rica when I was 24. http://www.tcu.gov.on.ca/eng/career/enrich.html
Student Science and Technology Online Research Coop - science.gc.ca/course - see coop department for more details
and that's probably just a start...
Contests
General Youth Information
Change the World/Volunteer Locally
https://www.youtube.com/watch?v=0sbG-172e_Y
Go global - work/volunteer abroad
Other
wemadeit.ca - an interesting resource for young women looking for role models of what it's like to be a woman in science/math/engineering