I don't think I have met a parent that hasn't had a hard time getting their little ones to help around the house. We tried everything from silly threats about taking toys away to time out. This always resulted in the girls breaking down into fits and Mommy and Daddy ended up cleaning up the house by oursleves. We had to come up with something. That's when we instituted the "Good Girl Jar".
It sits front and center on the kitchen counter. Next to it, is another jar filled to the brim with fuzzy-feel-goods (basically colorful pom-poms). Whenever the girls do something nice, like say pick up their toys, they get to pick a fuzzy-feel-good out of the jar to put in the "Good Girl Jar". When all the fuzzy-feel-goods are in the "Good Girl Jar" they get a special reward like being taken out for pizza, a new toy, or a fun family activity. Incentives work great with kids. They are willing to show you how hard they will work to earn that special prize. It becomes a game, and it helps Mommy and Daddy not have to resort to threats.