Schools definitely do matter, but their rank doesn’t necessarily mean anything. My 15 y.o. son attends our local school which is ranked outside the top 400. The majority of students aim for apprenticeships and retail industry jobs instead of applying to Uni so they aren’t academically focused, but we have a few teachers who used to teach at James Ruse & other selective schools, who are very supportive of motivated students. They enabled my son to achieve 98 in Advanced Maths last year. He is very happy with the recent Maths Extn 1 paper and already well into the Extn 2 course. His older sister achieved six band 6’s and two E4’s and got enrolment offers from her first choice med schools in every state.Yeah St Marys is going down every year. But in my opinion school definitely does matter in many ways. Compare a ranked 400 school and ranked top 10 schools, there will be a huge difference in resources, teachers, learning environment and cohort. That is why ranked 400 schools gets like 10 band 6's every year with like 2% success rate and top 10 schools with hundreds of band 6's/E4 with like 50%+ success rate.
A lot of people are so caught up trying to decide between selective & private schools that they don’t look into what their local school might have to offer. In recent years, a number of local kids have transferred from selective and private schools to our school because they realised that the increased travel time and higher school fees weren’t worthwhile.