Deut. 32.8 said:
Where we can justify the biocide of the Flood, the mark of Ham, the killing of the first-born prior to the Exodus, the genocide of the Midianites, and the ethnic cleansing of the Amalekites?
Where we can justify a backward attitude towards women?
Where we can characterize same-sex relationships as abominations deserving death?
Of course, we would not confront this ugliness were we to teach, say, the religion of the Deists, or the views of Spinoza's Pantheism, or perhaps the tolerance of Bahai. And we certainly would not face such ugliness were we to teach Confucianism or Secular Humanism or even Ethics.
Perhaps one of these latter options could be seen as a reasonable compromise. Somehow, however, I suspect that those who want the Bible in the class will strongly reject such an approach.