The card and coin challenge
You'll need one quarter and one playing card. With your palm up and index finger extended, balance the playing card horizontally on top of the finger.
Place a quarter in the middle of the balanced card directly over the tip of your finger. Tell your child that you can remove the card without touching or dropping the coin.
Wait for him or her to express doubt, then go for it. Flick the card sharply with your middle finger. The card will fly away and the coin will remain in place.
Colorvision crayon caper
Begin with both hands behind your back. Have your child give you five crayons so you can't see them. Turn to her, keeping the crayons behind you, and say you are going to name the color of each crayon without looking at them.
Take the crayons in the palm of your left hand. Bring one of the crayons to your left fingertips and secretly mark your right thumbnail. (Draw a small line across the face of the nail or scrape a bit of crayon underneath.)
Bring your empty right hand forward. Point to your daughter's palm, asking her to hold it out so you can return the crayon. As you do this, sneak a peek at your thumb, making sure you hold it at an angle where she can't see it.
When you see the mark, you'll know the color of the crayon you're holding in the fingertips behind your back. (Let's say it's red.) Put your right hand behind you again and grab the red crayon. Pretending to search blindly, slide a second crayon into your left fingertips and mark your right thumbnail with a new color. When the nail is marked, say, "I will now hand you the red crayon."
Bring your right hand forward and place the red crayon in your child's hand. As you do, sneak a peek at your thumbnail to determine the color of the next crayon ready to be grabbed. Repeat the process.
Hold the ends of a straw with the thumb and index finger of both hands, then rotate your hands over each other slowly. The straw will roll tightly around both index fingers, leaving a small section filled with pressured air in the center.
Lift your hands toward your child and ask her to curl a middle finger and flick the middle section of the straw. If she strikes the section solidly, there will be a loud pop, and the straw will snap cleanly in half.
(c) Copyright 2001. The Christian Science Monitor