Our son attended Balwyn High School and he loved it. We were also very pleased with the education he received there. Provided you live within the zone, enrolling is straightforward. There is also a high demand from buyers looking to buy in the area because of the school's excellent results year after year.
The best high school in Balwyn North would be of course Balwyn High School. This is a reason why properties in Balwyn/Balwyn North are expensive - because they are in the Balwyn High School Zone! Live within the school zone and you are virtually guaranteed a place.