Octa decagonal template

The website also has templates for a hexahexaflexagon. October 21st is Celebration of Mind Day , a holiday that honors Martin Gardner and his contribution to recreational mathematics. I like to show this 2 minute clip I found online of Martin Gardner demonstrating a hexaflexagon. Often, this date falls close to the day my students come back from Fall Break. I always talk about who Martin Gardner was. He did not invent the hexaflexagon, but he did tell the world about it. I first learned about hexaflexagons when I was in the tenth grade.

My sister was in the seventh grade at the time, and she got to make one in her math class. I was a tad jealous, and I was also extremely frustrated. And, she made it look so easy. One of my Statistics students is an amazing artist. This was her creation. I am inspired by it, and I just had to share! She puts my hexaflexagon to shame. Since this is already glued together, I decided to make another demonstration hexaflexagon. I printed two equilateral triangles 7.

This is just slightly smaller than my assembled one. They are truly mesmerized by them 3 Don't be disheartened by the 3rd class. It happens sometimes usually with the class you least expect it to happen with! Post Contents hide. Math is… Tweet Strips. Alphabetical Advice. Modular Origami — Sonobe Classroom Display. Camel Crossing the Desert Puzzle. Tombstone Project. Graphing Ordered Pairs Foldable. Click here to cancel reply.

Stephanie Friday 15th of May Group dynamic. You need that ONE child who gets excited to rope the rest into the fold. Create an account. Edit this Article. We use cookies to make wikiHow great.

By using our site, you agree to our cookie policy. Cookie Settings. Learn why people trust wikiHow. Download Article Explore this Article methods. Tips and Warnings. Related Articles. Article Summary. Method 1. Determine the side length of your octagon. The larger the length of the octagon's sides, the larger the octagon itself.

Make a decision based on the amount of room you have to draw in. Use a ruler to draw a line of the length you decided upon. This will be the first of the eight sides of the octagon. Draw your line in a spot that leaves plenty of space for the rest of the sides. Using a protractor, mark an angle o relative to your line. At either end of your line, find and mark the o angle.

Draw a line of the same length as the first line angled degrees to the original line. This we be the second side of the octagon. Note that the lines should meet at their end points. Don't start the new line in the center of the old line, for instance.

Continue creating lines at o angles to the last line. Follow this pattern, drawing lines of the same length that meet at o angles. Repeat these steps until you have created a complete regular octagon. Usually, if you've drawn carefully, it's acceptable to use a ruler to simply connect the end of the seventh side to the beginning of the first.

Method 2. Draw a circle and two perpendicular diameter lines. Compasses are simple tools used to draw perfect circles. So, a larger circle will produce a larger octagon, and vice versa. Use a compass to draw your circle, and, after doing so, draw two lines that stretch across the diameter of the circle and meet in the center at perpendicular angles. Make a slightly larger circle centered on the same point as the original.

Keeping the point of the compass on the same point, draw a circle with a slightly larger radius setting. For instance, if you originally set the radius to 2 inches 5.

For the rest of this process, keep your compass set to this new, slightly larger setting. Make an arc across the center of the circle. Place the point of the compass on one of the intersections between the inner circle and its diameter. Use the compass to draw an arc near the center of the circle. You don't need to draw an entire circle - just an arc that stretches from one side of the circle to the other.

Repeat for the opposite side. Place the point of the compass on the intersection between the inner circle and its diameter line opposite the point you just used and draw another arc across the center of the circle.

You should be left with an "eye" shape in the middle of the circle. Draw two lines that pass through the corners of the eye. Use a ruler or a straightedge to make these lines. The lines must be long enough to intersect the circle in two points and should be perpendicular to the diameter line they pass through.

Draw two arcs from the remaining points of intersection between the inner circle and its diameter lines. Next, repeat the previous steps for the other diameter line that forms the central cross. In other words, place the point of the compass at the intersection points between this line and the circle and draw arcs stretching across the center of the circle as before.

When this is done, you should have two intersecting "eye" shapes. Using a straightedge draw lines through the corners of the new eye. As before, you'll now want to draw two straight lines through the corners of your new eye shape.

The lines should be long enough to intersect the circle and should be perpendicular to the diameter line they cross. When drawn, these lines, together with the lines through the corners of the other "eye", should form a square. Connect the corners of the "square" just completed to the intersection of the central cross and the inner circle. These points just mentioned form the corners of a regular octagon.

Connect them to complete an octagon. Erase the circle, lines, and arcs, leaving the octagon alone. You've just drawn a regular octagon! Method 3. Start with a square piece of paper. Folding a perfect octagon from a sheet of paper means starting with a square sheet. This means you'll need to find a square sheet of paper construction paper often comes in this shape or trim one edge of your paper to make it square.

Fold the corners of the square inward. Notice that, as you do this, you create an 8-sided shape. These folds will serve as four of the eight sides of your octagon, so, for your octagon to appear regular, it's important to ensure they're the correct size.

Use a ruler to measure the folded edges - you'll want any two edges to be as close to the size of the space between them as possible. Note that you shouldn't fold the corners all the way in. If you do, you'll be left with a smaller square. Instead, fold the corners in about halfway to the center.