Educating Risa

In addition to Fact Flowers, which are quite simple and self-evident, we also made Difference Diamonds, a more complex idea and one that creates geometric art. Begin with a reasonably large, square piece of paper. Choose four numbers between 10 and 20 and write them in the corners. (You’ll want to do this on regular paper first, drawing subsequent diamonds/squares in pencil, before cutting out coloured squares / diamonds as I am doing below.):

Now add a diamond (or draw a diamond), whose corners come halfway between these first four numbers. Take the difference between the numbers and write the answers in the corner of the diamond. (18-10 = 8, so I write an 8 on the diamond corner at the top, between the 10 and 18, and so on around the diamond):

Now add (or draw) a smaller square inside the diamond, and again write the difference between the numbers in the appropriate corner:

Keep going, adding (or drawing) diamonds and squares, and writing in the difference, until you get to a point where the difference of all the corners is zero:

Try a few, and see if the answer in the middle is always zero. Note that difference diamonds can vary in the number of steps. Here’s a couple others we did:

You might also notice that I have folds on the paper to help me in drawing my diamonds and squares neatly. The paper needs to be folded in half, both horizontally and vertically, as well as on both diagonals (bottom right corner to top left corner, making a triangle, and vice versa). When drawing, the corners of subsequent diamonds / squares always land on a fold.

I’m really pleased with the start we’ve made on our ‘math art’ wall: