A private Lutheran school expelled two girls, high school juniors, for violating the code of conduct when - according to an article in the San Francisco Chronicle - the school principal learned that the two were engaging in a lesbian relationship.
The girls (or their parents) have filed suit against the school, claiming they violated the Unruh Act, which prohibits businesses from discriminating on the basis of a person's actual or perceived sexuality (similar to the recent Illinois law). Now - in spite of constitutionally protected freedom of religion and freedom of association - both a California appeals court and the California Supreme Court has agreed that the girls may have a valid suit. So the school will at least face thousands of dollars in legal fees and at worst be directed to accept homosexual students or staff.
Look out - if it can happen in California, it can happen in Illinois.