Wow! Cathy, That's exactly what a psychologist in social skills group session we attended told us(desperate parents) to do! No long explanations, lectures or negotiations. He said we should use natural consequences and positive reinforcements. Be consistent and make sure to follow through what you say or do.

We also watched the video called 1-2-3 Magic in the class.
http://www.parentmagic.com/
It was interesting.