Here is a set of educational paper toys: Remember the papercraft alphabet? Ever since I published it, there have been requests to complement it with a set of numbers. I finally got around to designing the numbers.
These are not plain and simple numbers, either, but they come with a trick: Each number has a depth proportional to it’s numeric value. So two is twice as deep as one, three is 1.5 times as deep as two, and so on.
That means that it’s very easy to do math with these numbers, in particular subtractions and additions. It’s so easy, in fact, that my 3 year old son (who knows what the numbers look like, but can’t actually add or subtract) spontaneously started doing math with them. This is how it works:
Here is a video of my son adding 1 plus 3, and then more (in German, but I have added captions):
Here is the rest of the gang:
You will notice that each number has it’s own, distinct color. The colors follow a gradient, so that similar numbers have similar colors. Each number has the corresponding word printed on the front. This also helps to decide about the orientation of 6 and 9.
I also made a ten:
The ten is very useful for results greater than 9, as you can represent, say, 15, by putting 10 and 5 next to each other. And it has stripes corresponding to the individual numbers, which again helps to bring them into the correct sequence.
The numbers have a ‘blocky’ look. This is for two reasons: First, perfectly rounded numbers would not stand on their own. And second, they are much, much more difficult to build. Believe me, I’ve tried. In fact, I had a complete set of non-blocky numbers which was so finnicky to assemble that it just wasn’t worth it.
As for the holes in 6, 8, and 9, you can actually leave them in there, as it’s somewhat difficult to cut them out, but if you want to remove them, use a sharp Xacto knife and be careful.
If you make these from >150 gsm paper (53 – 82 lb bond/ledger), they will be quite sturdy.
I have made eight sets of templates: Ones with and without the names of the numbers on the front, colored and outlined, and with proportional depth and fixed depth:
- Numbers with proportional depths, colored, with the names of the numbers printed on the front
- Numbers with fixed depths, colored, with names
- Numbers with proportional depths, outlined (i.e. white; these can be used for coloring by hand or just ‘as is’), with names
- Numbers with fixed depths, outlined, with names
- Numbers with proportional depths, colored, without names
- Numbers with fixed depths, colored, without names
- Numbers with proportional depths, outlined, without names
- Numbers with fixed depths, outlined, without names
The ones with fixed lengths are more for display purposes or to complement the alphabet (where each letter has the same length).