I had a number of parents ask me about how combined grades classrooms are set-up and how they run. After searching the ministry website, I have posted a pamphlet entitled, "An Introduction to Combined Grades" in pdf format on the left panel under "All about Curriculum". There is a brief summary of what a combined grade is and ways that it can benefit your child and how you can help his/her learning.
If you can't find the link for any reason, here it is again:
http://www.edu.gov.on.ca/eng/parents/combinedClassrooms/index.html
Hope this helps!
Mme Dungo