Teaching kids the value of a dollar starts with teaching them the value of a penny. “Use spare change to pay kids’ allowance for chores around the house,” says Eric Tyson, author of Personal Finance for Dummies (Wiley Publishing, $15, www.amazon.com). Then they can see how it accumulates into dollars, fives, tens, and eventually a new game for the Xbox. (Never again will they throw away a penny with their receipt — and you won’t, either.) Change can also be a great hands-on tool for teaching youngsters math. “Use coins for adding practice,” suggests author Judy Lawrence. Let the kids keep the coins if they solve the equations correctly.