Dotsie:
Our children, whatever age they may be, also need to be respectful of our work. I know it's harder when you're a stay at home mom, (I am one too)cause they tend to disregard it as real work. But it is important that they take it seriously. So I do think that giving notice in advance would definitely work.

Also, when you let them know you're not available cause you are working it helps them view your work more realistically. Don't feel guilty. If you were at a 9-5 job somewhere else, they would seek other means of transportation!