Crusades Spanish Inquisition Oppression of gays and minorities Death for adultery, lying about virginity, rape victims, homosexuality
Versus
Science The Enlightenment
As long as though show what the Christian books actually say and how religion has been a tool of oppression (as is Islam), then I would not be so concerned. I know my daughter does some comparative religion in primary school and has visited a church, temple, mosque etc but she does ethics instead of scripture.
In ethics, they discuss views on what is right and what is wrong. In scripture, it's "who doesn't believe in Jesus. You're going to hell."