For the most part, while teaching, you will be expected to stick to your plans. You never know when you may be randomly observed, and it will be expected that you're teaching what you said you were going to teach. It's important to demonstrate your professionalism and discipline by showing that you can stick to a plan regardless of how you feel or what happens. On the same token, flexibility is also important. This question offers a great opportunity to share about a time you either stuck to a plan or veered away from your plan due to students' needs, curiosity, or a teachable moment presented itself.