Changing demographics and a growing urban population brought about the death of the homogonized country schools and necessitated a much bigger public school system. When you have children from many different backgrounds and faiths all learning in the same place you obviously have to be avowedly secular.
By the way, do you also favor eliminating chaplains in the military? Your taxes pay for them, too.
Military chaplains are a different situation. Chaplains provide beneficial spiritual guidance for those who want it, but no one is required to participate in any sort of religious service. They fulfill the same function as a parish priest.
These changing demographics took place well before the 1960s, especially in urbanized environments. It seems people were able to work out on their own what they wanted in their school curricula without judges imposing it on them.
Chaplains provide beneficial spiritual guidance for those who want it, but no one is required to participate in any sort of religious service.
No one suggested requiring schoolchildren to participate in religious activity. That doesn't mean schools are somehow constitutionally obligated to censor their curricula to avoid offending small minorities.