Sunday 17 December 2023

Sunday 17 December - Advent 3 Papercrafts - Flexagon

This might be a bit fiddly, but bear with me - I did make these with my Sunday School class of 5-9 year olds. The older children helped the younger ones, and the adult helpers marvelled at their achievement.

It comes from this book which has given me a lot of pleasure 


You need a strip of paper cut in the ratio 1:7, so 1 inch wide and 7 inches long will do. You will end up with a magic hexagon this size;


Magic? It has three faces!

You also need scissors and a glue stick.

At the top of the picture is my strip. It's one I folded earlier, which is why it is creased. Take the LH edge, and fold it over at an angle of 30 degrees - you can do this by eye. What you are after is folding a series of equilateral (all the sides the same length) triangles. The angle is slightly less than half of the right angled corner.

Fold a series of equilateral triangles, accordian, or zig zag, style following the pattern of creases on the middle strip. This means that the words 'fold this edge' wil line up UNDERNEATH the words 'to here'. 

You end up with this springy thing. Open it out - you don't have to number the triangles but I've just done it to show you. Cut off the red areas, once you have made sure that you have 10 triangles!


Fold it back up again, and just open it a bit like a book so the two ends are on the left an the right. Put the glue on as shown, and fold it closed, like the top of the next photograph.


As you try and unfold it, you will find that you can ease it into the form of a hexagon!

Now here's the thing; should you decorate one side (I coloured it blue) and the other side (I coloured it red), you can bring the points to the middle and open it out to reveal a white, uncoloured side!


So there you have it. A piece of paper with three surfaces.

What can you do with it? I have no idea. They make a good fidget toy, or some kind of magic trick. 



3 comments:

  1. I adore hexaflexagons. If you plan them carefully, you can arrange different messages and pictures to appear as you flex the faces. Martin Gardner, American mathematician, is the expert in these. Thanks for the reminder - It's about time I taught Rosie (useful diversion oved Christmas methinks)

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  2. I wasn't sure if any of my readers would be up for a flexagon! This is a much simpler version than any I found on the Internet. If you manage to sort of unfold it you will be able to see that it's a sort of flattened mobius strip (another treat for Rosie).
    I did them with the Sunday School for Trinity Sunday.

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    1. Rosie and I did moebjus strips in the summer!

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