As an objection to Christian education, I hear that parents want their children to be salt and light in the public schools. In Matthew 5 Jesus tells his audience to be involved in the world so that the salt and light is clearly seen. When they see your good works, says Jesus, they will praise God.
The assumption of Christian parents is that they have Christian children who are able to carry this out. Jesus is obviously addressing people who have reached spiritual maturity. What I see is the thrusting of children into the public sphere before they are disciples. They are not salt and light because they haven’t got the maturity.
Of course, mature Christians should redeem the public schools and make them the Christian bastions of truth that they once were. However, before leaping into public education ask yourself whether the one being thrusted actually IS salt and light. If the child is mature enough to shine, if the adult is truly a disciple, there is a case for letting their light shine before men so that they may see the good works and praise their father in heaven. If the child is still just that, a child, do not be surprised when the good intentions backfire and the child falls away through an internal conflict that was never anticipated.
There is no neutral instruction. When is a child salt and light enough to counter the hedonism, naturalism, postmodernism and nihilism that they will receive?