My daughter seems to be a fairly quick study. I just went with the flip change. She threw some good ones and she threw some high ones, short ones, but she did manage to throw a bunch in the strike zone. She followed up with good fastballs after each change. She is a young 8yr old.
I am going to look at the Bob Todd videos.
It's worth checking out IMO. You can get the whole DVD for about what a 30 to 60 minute lesson will cost you.