It isn't "leftism" to put religious mythologies in a mythology class. It would be leftism, however, to "feel" for the other side, be politically correct, and allow unscientific stories be taught as science.
Be careful, you're putting the whole field of climatology at risk.
"It isn't "leftism" to put religious mythologies in a mythology class."
As a matter of fact, it is. Hard core leftism. The destruction of religious faith is one of the core items on the left's agenda, and relegating religious beliefs to the status of "myths" is undeniably a move in support of that agenda.