I personally don't see how the lack of God has somehow demoralized public school . . . mandatory prayer was long gone by the time I was in school, but honestly, there was never any problems in elementary school. Middle school and high school were different stories, but middle school was a special case, because it was in the ghetto. High school was typical high school: yes, there were some immoral activities going on like smoking in the bathroom, teen sex and pregnancies and such, but we can't really blame it on lack of God for two reasons. 1. This is what high school is like - it has been for decades, and will probably continue to be this way - this is the age that teens like to rebel against the establishment. 2. This will continue to happen whether God is in their lives or not . . . my sister's always had God in her life, and she was fairly close to be a stereotypical teen girl when she was that age, and she continued to rebel even into the Genesis of her adulthood: she did drugs, she partied, she had her firstborn out of wedlock.
Private schools and homeschool are often far more faith-based, but even that wasn't immune to some of the immoralities of society . . . I remember in my science class in Grade 9, one of my classmates was quite practically the Eddie Haskell of my generation: always acting up, always goofing off, always being a wise guy, but would put up the polite facade when speaking to the teachers . . . but my Eddie Haskell had an incredibly, incredibly perverted and raunchy sense of humor - and thinking on it now, I bet HAPPYTIME MURDERS would be right up his alley, lol.
Reading the article, I can understand the person's feelings that whether or not God is in somebody's lives is up to the parents and families themselves, but at the same time, I don't see the harm in the motto "In God We Trust" being on public display in schools either - as pointed out, it's already seen everywhere else, from our money, to government agencies, and such.