One issue that wasn't mentioned is the fact that because the California school system is so large, textbook publishers will have to make their textbooks fit the California curriculum or risk losing the sales to the largest market. Those same textbooks will be sold to schools all around the country. So, essentially, even if you live in a different state, if your child goes to public schools, they might be influenced by this decision. Parents will likely not know, because parents do not generally read the textbooks issued to their children.
"Be of good comfort, Master Ridley, and play the man! We shall this day light such a candle, by God's grace, in England, as I trust shall never be put out."
--Hugh Latimer, October 16, 1555