Here's what I found on the CA Dept of Education website:
Q.5. May a charter school offer, provide, or teach religious curricula? If it does, is the school still eligible for apportionment?
Charter schools and non charter schools may teach about religion, but may not teach a sectarian curriculum. EC Section 47605(d)
https://www.cde.ca.gov/sp/cs/re/qandasec4mar04.asp#q5
So no, they can
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Recovery Board