While Carnegie may have done that, even the Unitarian (a religion that effectively denies Christ and the Divine authority of the Bible, but, unlike its immoral form today, at that time it at least overall upheld general Biblical morality) “Father of the Common School,” Horace Mann (May 4, 1796 — August 02, 1859), who became Massachusetts Secretary of Education in 1837, not only understood the impossibility of separating education from religious moral beliefs, but held that it was lawful to teach the truths of the general Christian faith, asserting that the “laws of Massachusetts required the teaching of the basic moral doctrines of Christianity.” Mann, who supported prohibition of alcohol and intemperance, slavery and lotteries, (http://www.famousamericans.net/horacemann) dreaded “intellectual eminence when separated from virtue”, that education, if taught without moral responsibilities, would produce more evil than it inherited. (William Jeynes, “American educational history: school, society, and the common good,” p. 149, 150)
To critics who were alarmed at the concept of secular schools, he assured that his system “inculcates all Christian morals; it founds its morals on the basis of religion; it welcomes the religion of the Bible...,” but he did exhort that Bible reading be without comment to discourage sectarian bickering. (Mann, Twelfth Annual Report for 1848 of the Secretary of the Board of Education of Massachusetts. Reprinted in Blau 183-84.
Translation: Mann wanted education that was lukewarm, generic, with Bible reading without comment.
So?...What do the students in this environment learn? Answer: They learn to be generic, lukewarm, and noncommittal regarding their faith.
What does Christ do with the lukewarm? Answer: He spits them out of His mouth!