When you send your children to public school in Toronto (or Mississauga, or neighbouring municipalities) they will automatically be sent to the school closest to them. This is something for you to consider when you choose where to get an apartment or house. Most Toronto public schools have a high standard of education but certain neighbourhoods are better than others.
It is the unfortunate truth that in certain low-income neighbourhoods, the classrooms tend to be more overcrowded, the teachers less experienced (teachers with more seniority might request to be transferred to less difficult neighbourhoods), and the classmates less successful. I suggest when you are looking for apartments or houses, you ask the realtor or landlord where the closest school is, and before you sign a lease or buy a home, you go to the school. Ask for a tour. Most of the time the school will gladly show you around. If you go at the end of the day, there might be other parents there picking up their kids (some kids will walk alone or take the bus but usually at least a few parents will go) and you can ask them their opinions about the school.
Also note that you do have the option of sending your child to a school not in their neighbourhood. This is under the policy called "optional attendance" - where you opt to send them to another school. However, this is only possible if that school is not full. Remember, it might be annoying for your child to have to take the bus or commute to a school further away; they won't live in the same neighbourhood as their friends.
Finally, note that in Toronto, there are a number of "speciality schools" - schools that offer French immersion, education focussed on the arts (heavy offerings in theatre, drama, visual arts, music), or other "alternative schools" - much info is on the TDSB website. You could try to enrol your child in one of these schools - they are usually excellent. There is also the Toronto Catholic District School Board - you don't HAVE to be Catholic for your child to go there in the upper years.
