Anonymous wrote: Be honest "I'm sorry but I just don't think that I am a good fit for this job" follow up with something like "your children have so much enthusiasm and I am really going to miss them. This is my two weeks notice, or whatever.
I wouldn't go into how stressful you find it, or how crazy the parent seem. Its not like you will use this lady as a reference or anything so you just have to stay calm and polite. Feel free to say sorry a bunch of times.
I too think that sounds really stressful. One of my charges was having a rough week last week and was only napping for tiny amounts of time, and I too found that really stressful. I really do need 25m in the middle of the day to eat some lunch, have a cup of tea and take a couple of deep breaths.
+1 to everything PP said. Apologize, be professional, and resign. I couldn't do it either, that sounds VERY intense.