There was nothing about the textbook in that article. You know I wouldn't countenance a textbook that whitewashed Moslems any more than I would one that whitewashed Christians or even Jews.
True--I would have a problem playacting, e.g., a nativity scene in public school .I just told you I had a problem reciting the Lord's Prayer. BUT--and this is a big but--it really depends on the spirit in which it is done. If it is done as play, as something not "real," and as something essentially isolated in the curriculum--that is, over a 3 week period, like that Islamic thing was--as opposed to something that is done every day or every week, and with obvious "devotion" (or the pretense of such),--then I would not have a problem with it.
The spirit in which something is done is crucial. What is appropriate and even essential in a church or a synogogue or a mosque is inappropriate in a public school.