## Introduction: Twenty Sided Ball Made From Greeting Cards

It hasn't rained here in months, but every once in a while you just have to have a rainy-day project that recycles greeting cards. This finished ball is just over 5 inches (13.5 centimeters) in diameter.

## Step 1: Gather Materials

You will need:

1) 20 greeting cards

2) scissors

3) 31 paper clips

4) jar lid (mine was just under three inches (3" or nearly 7.5 cm)

5) ruler or straight edge

6) pen or pencil

7) glue

8) string - twelve inches or 31 centimeters is plenty

9) one sheet of notebook paper

10) compass (Don't panic. It is used only to score the cards for folding.)

## Step 2: Draw and Cut Out 20 Circles

Using the lid, place it over a part of the card you want to use and draw a line around the lid. Cut on the line. Repeat to make 20 circles all the same size.

## Step 3: Make an Equilateral Triangle Template

You need to make three points equidistant from each other (an equilateral triangle) on the circle.

Take a sheet of notebook paper and using the jar lid, draw another circle. Cut out the circle and fold in half. Unfold and draw a line along that fold. Position the circle with the line running from top to bottom. Fold the bottom half up to the top half matching up the lines. Unfold and again position the circle with the line running from top to bottom. Fold the bottom edge to the middle fold line again matching the lines. Unfold. The top edge where the fold is and the lower two fold points make up an equilateral triangle.

Draw another circle and mark these three points on it, circling the points to make them stand out. See photographs for clarification.

## Step 4: Mark the Circles

All the previous nonsense was so you can use the template you just made to mark all the circles quickly for their scoring and folding. Place a circle on your template and make a small mark on the circle where the folds should be. Yes, my template is different. Trying to use the silly compass to make an equilateral triangle just didn't work out. For each of the 20 circles, mark all three points.

## Step 5: Score and Fold.

Line up the ruler connecting two points and score a line between the two. Do the same for three sides on each of the twenty circles.

Fold up the three edges of each of the circles following the scored lines. The folds are not supposed to be pressed down flat, just a valley fold.

## Step 6: Arrange Circles

Arrange five circles to form the top, then ten for the the middle and five more at the bottom. Here is where you can get artistic with the color arrangement or just let the pieces fall where they may.

## Step 7: Start Paperclipping Together

Start with the string and the five circles that will make the top. Tie the string onto a paper clip just so it doesn't pull out so easily. With the string being at the middle point, paper clip the folded flaps together. The middle point where the string comes out will have the corners of all five circles coming together. This is where all these flat circles begin to take on a three dimensional shape. Do the same with the bottom five circles.

## Step 8: Paperclip the Middle Row

For the middle part, paperclip the folded flaps together to form a flat row, then circle them around and connect the two end flaps to make a three dimensional ring.

## Step 9: Paper Clip Top and Bottom to the Middle

Now it is just a matter of paper clipping the top with its five flaps to one side of the ring that is the middle row. Once that is done, turn it over and paper clip the bottom five circles to the rest of the project.

## Step 10: Double Check and Glue

Just double check that you have the circles in the right places in relation to the others. If you have a color pattern you are trying to work out, like green on top and bottom and red in the middle, for instance, now is the time to check them before you glue it all together.

Once you decide that all the circles are in the right places, take off five adjoining circles and glue their flaps to each other. Put the paper clips back on just until they are dry. Keep the points close and neat.

Don't forget the string. Along with the paper clip, a fair size drop of glue on the string on the inside of the ball should keep it from slipping out.

Glitter and sequins are not my thing and not on my list, but could certainly add that bit of joy that so many kids love.

This can can also be put together with all the flaps on the inside, making a regular icosahedron.

## 10 Discussions

Easy and thank you!!!

You are welcome! I hardly remember doing this!

I have a gamer brother who would love this as a gift. I just need to draw numbers on the sides... ^^

That would be easy enough. I would do it before cutting and folding and gluing. Good luck!

Fun, creative, educational, and uses recycled materials. Perfect!

Thanks! (Gee, it's great to do something perfect now and again!)

The proper term for a twenty-sided figure is a "Dodecahedron" Just to shorten up the title ;) Great idea otherwise! this would make excellent Christmas ornaments! 4/5

Dodecahedron is a 12 sided polyhedron. The proper term is icosahedron. See http://www.georgehart.com/virtual-polyhedra/naming.html where it states. "Similarly, icosi-, meaning 20, is used in the 20-sided icosahedron."

Ahah! Pardon me for my misconception prior to your previous comment. :D

It's a great idea! But just to prolong the reply list: Sorry no dodekahedron :-] The correct name would be "ikosahedron" because greek "dodeka" means twelve and if you count the triangles of top bottom and middle row, there should be twenty - greek "eikosa" -triangles! And by the way, if one reads until the end there is even written in the last sentence which platonic solid is made by this work ;-)