what does this part of the stanford common app affirmation mean?

on the affirmation, there’s a confusing part to me, stanford has the right to rescind if you"alter your class/course with approval from office of undergraduate admission." Does this mean high school courses as well. I need to get permission with stanford?

yes. you have to ask them, as their decision was based on your current schedule being completed. Not unusual.

It means you can’t state your last semester as full of honors and APs and then, quietly drop them and be a slacker for your last semester. This isn’t on your plans, right?