Pregnancy Class does not equal Science

How have you kept your cool when attending pregnancy classes that either have (a) outdated information (b) wrong information or (c) information that go against your own personal beliefs? With A and B - I just received reading material for tomorrow's birthing class that I am attending, and I'm given great (awful) information about co-sleeping and PFM training. I feel like I just wasted $400. Grumble grumble.

Quick edit: the class turned out to be nothing like the reading material, it turned into a 7 hour anatomy/massage/post birth class taught by a post birth doula that actually made sense, even if we didn't agree with everything. The reading material made it look like it was something totally different than what it turned out to be.