How can public school elementary teachers add spiritual components and biblical history to their curriculum in a legal way?

How can public school elementary teachers add  spiritual components and biblical history to their curriculum in a legal way? What legal cases support your claim? Give evidence in a  900-word count (min)  APA format essay.  Add at least 3 of the 4 components: Graphs, Charts, Pictures, Timeline,  or Several related Quotes, components can not be included in the word count. Resources in APA format. Information (not quotes) must come from references no older than five years.