Christian school principal Robert Duiker considers the public character of Christian education in The Banner, and closes by saying,
All schools—whether they are publicly funded or not—that build citizens by teaching an official language, by training in skills for the workforce, by nurturing ingenuity, by supporting physical well-being, and by teaching the government approved curriculum, are part of a system of public schools.
Whether they are funded or not, Christian schools are public schools.
Mr Duiker is right that at least some Christian schools participate in a societal public school philosophy. The heart of that philosophy is the notion that schools belong to the community (thus “public”), and historically the schools within the old Dutch settlements adopted something of this line.
Two items erode that understanding: the notion that schools are family based, and the rising tuition. The latter is especially cogent, since it begins to restrict the ability of the school to serve a wide socio-economic swath of the community (another value of “public” education). This burden of cost and tuition pushes the schools away from supporting communities and toward the sending homes. This is more individualized and far more market driven.
The family-based philosophy of the past generation further reinforces, even sanctions this move up the socio-economic ladder. From the very beginning of the public school movement in the United States, the schools were contrasted with the European and aristocratic model of family-centered education.
However if some follow a public philosophy, others do not. Short of government support (high unlikely in the U.S.) the socio-economic pressures are likely to push more and more Christian schools into a functional private school model, this independent of the desires and efforts of faculty and parents.
Lastly, the functional difference between public and private is as much about governance as it is about philosophy. A public school is one that has institutional accountability to the community at large. It is hard to see how a philosophically focused school can participate in such a system without compromise, no matter how open it is, or how well it teaches patriotism.