Yes, you know they should wash those dirty mitts often, but what you really need to know is how to get them to do it sans whining. We've got some tips and tricks for making washing up fun:

• To get them to soap up for the required 20 seconds (or more), belt out "Happy Birthday" twice. Everyone sounds better in the bathroom anyway, right? 
• Fill the sink with water, and let them go to town with foam soaps and bath toys. (Ignore the water on the floor.) 
• Lather up, Mom! Be a good example for your kids, and encourage them to "teach" their dolls to wash up, too. 
• Make sure they can reach the sink easily. If you don't have one already, get a colorful stool to give them a boost. 
• Keep their fingernails clipped -- less real estate for germs!