# Mobius Strip Ornament

Artists and mathematicians have a long history of developing impossible shapes and forms that can’t exist in reality, but there’s one “impossible” object that you can easily make at home: The Möbius Strip. It’s a three-dimensional shape with only one side, and it’s perfect for holiday decorating!

Ages:
9 - 16
Est. Time:
<30 mins

# Materials List

1. ribbon - about 1" wide
2. scissors
3. tape or glue
4. string

2. To make the most of observing how cool Möbius strips are, we highly recommend finding a ribbon with different looks or textures on each side. Cut a length of ribbon (about 6 inches). Bring it around in a loop, then give one end a half-twist. That’s what gives the Möbius strip its unique shape! Connect the ends of the loop with tape or glue. You should be attaching the front side of one end to the back side of the other.

3. Investigate your strip. How many sides does it have? If you run it through your fingers, or draw a line along it with a pen, you’ll cover the whole band (inside and out) and then get back to where you started! The twist in the ribbon means that it only has one surface, not two like a normal ring. This can be really useful; conveyor belts and other machines are shaped like Möbius strips so that they’ll wear out evenly--they last twice as long as a regular band!

4. Try cutting your strip down its length (try to stay in the center of the ribbon as you cut!). What do you think you’ll get? Two strips?

5. Actually, you get one big loop--it’s twice the length of the original! If you look closely, you’ll see that the loop now has two full twists in it, and that it now has two sides. Cutting it in half gave the strip its second side back!

6. Now that you’ve got the basic shape down, it’s time to see what else you can do with it! Try making a loop with a full twist instead of a half-twist, or with multiple twists. You can even thread the ribbon through its own loops!

7. Here are some of our favorite Möbius strip shapes.

Once you’ve got a shape you like, secure it with tape or glue. Loop and tie a piece of string through each shape to turn it into an ornament. Now you’re ready to decorate with the power of mathematics!