I have no problem with it. What's wrong with teaching students that the families their classmates come from are ok -- is it better for those students to be teased and harrassed? I would hope schools would teach my children that all families are acceptable. I don't think tolerance is anything to fear. I was raised by a single parent, and I bet back in the day, there would have been a similar outcry about letting kids think it was acceptable for a child to be raised by just a mom.
I do, however, question what the curriculum actually says, though, since I think the source of this article is not neutral. The source proclaims: "The Trumpet uses a single overarching criterion that sets it
apart from other news sources and keeps it focused like a laser beam on
what truly is important. That criterion is prophetic significance. The Trumpet
seeks to show how current events are fulfilling the biblically
prophesied description of the prevailing state of affairs just before
the Second Coming of Jesus Christ." (http://www.thetrumpet.com/index.php?page=help&q=about)
ETA: I also don't think it's teaching kids about homosexuality, how to be
gay, or that they should be gay. It seems a lot more like "kids come
from lots of different families and that's ok!" I think it's more
about accepting their classmates than it is about any kind of
sexuality.