The Church has always taught that parents are the primary educators of their children in the faith. And the primary way to teach one’s children the faith is to live the faith—to go to Mass each week, to pray each day, to do spiritual reading, and to discuss religious issues and matters at home. If parents do that than it is possible for them to send their children to a less-than-perfect parochial school or even to public school and CCD and still have them grow up to be good Catholics. If parents don’t practice the faith or discuss it often with their children, it won’t matter where they send them to school because the kids will grow up thinking that religion isn’t an important part of daily life let alone the most important part.
You are absolutely correct. Let’s not forget that there are many of us for whom Catholic schools are simply not an option. We live in a rural area. There’s no Catholic schooling available here, but we teach the kids the faith at home to the best of our ability and send them to CCD as well.
And if you think that all you have to do to ensure that your kid grows up in the faith is pack them off to Catholic school, you are dead wrong. My brother went to a very prestigious Catholic high school, and the last time he saw the inside of a church was at his wedding twenty years ago. I was a public school kid with a crappy “spirit of Vatican II” CCD program, and by the grace of God, I am the one who is a practicing Catholic.
Catholic schools are great, but they are not a panacea. Kids need Catholic families more than they need Catholic schools.