I've been a teacher (most of the time a college professor) for...a long time. Nowadays, when preparing a new course, I definitely work with AI: "Here's what I want, and who my audience is - give me a course outline".

That gives me a starting point. Of course, I modify it. Maybe I bounce back and forth to the AI for further refinements and suggestions, but ultimately I have to be happy with the result.

When prepping the individual lessons, the biggest time saver is coming up with examples to illustrate particular points. I could do this alone, but sometimes that involves staring at a blank screen for a while. It is faster to ask the AI for suggestions, pick the one I like, and refine it further myself.

AI is a tool. Use it appropriately.