When you drop a coin, you have a fifty-fifty chance of getting heads. When you drop a pair of coins, you can stack them in a way that also stacks the odds. The coin that starts out on top ends up on the bottom 100 percent of the time. You can't lose! You will need: 2 quarters, a nickel

Make a sandwich of the coins with the nickel in the middle. Hold the stack between your thumb and index finger so the coins are horizontal.