How do I talk to my kids about behavior that is not their true selves? How do I not condone the behavior but show acceptance?

The best way to do this is to communicate directly with your kids your thoughts on the situation. Start off with affirmation of who they are the values they have embodied and all the positives that you have observed discuss the negative behaviour or attitudes you have also observed. Discuss the scenarios with them and ask their thoughts on the issue and their responses in the situation then share your thoughts and feelings about the situation. Be very clear that your disapproval is with the behaviour and not with your kids. Give them opportunities to express empathy for te other persons involved and express your confidence in their ability to make right choices if they take the time to think things out.