If you have a code wheel, you and a friend can pretend you're secret agents and send each other secret messages. You'll use a code that only the two of you can understand. You also might use your code to write entries in a diary or journal. Your secrets are safe!
What You'll Need
Poster board or two small paper plates
Ruler or compass
Brass paper fastener
How to Make a Code Wheel
Step 1: Cut two circles, 6 inches each, from poster board. (You can also use two small paper plates.)
Step 2: Cut a 1/2-inch-wide V-shape and a 1/2-inch-round window in one circle wheel, as shown.
Step 3: Use the pencil to poke a small hole in the center of both wheels. Attach the wheels with a brass paper fastener.
Step 4: Write the letter A in the V-shape opening, then turn the wheel 1/2 inch and write the letter B. Continue with the rest of the alphabet around the wheel.
(Hint: You can measure 1/2 inch without a ruler. Make a small pencil mark on the right side of the V, then turn the wheel so the left side lines up with the mark.)
Step 5: Now fill in the window. Turn the wheel. Write the letter A in the window. (Make sure the V-shape is not pointing to the letter A -- then there'd be no code!) Turn the wheel several inches and write a B in the window.
Step 6: Place the rest of the alphabet in the window, always making sure the window letter is different than the letter in the V-shape opening.
Make a second wheel for your friend that matches yours exactly so you can write and decode secret messages.
Later, challenge your friend to a marble race through a maze. Learn how to make a box maze on the next page.