Ohio father Doug Hermann, frustrated by his son's math homework, posted an image on Facebook showing a check to his children's elementary school written out using "common core numbers."
Douglas Hermann/Facebook
Herrmann appears to be referencing a tool called "ten-frame cards" used to teach children basic facts about small numbers.
The idea is pretty straightforward: Draw a set of ten boxes arranged in two rows of five, and provide children with a bunch of small tokens like coins or buttons. Then, numbers can be represented by putting tokens or making marks in the boxes. Here's a ten-frame with three marks on it, representing the number 3:
The cards are intended to provide a visual and hands-on way for kindergarten and first-grade age children to develop their "number sense," or an intuitive feel for the basic facts of numbers, arithmetic, and place value. A child can look at the card above and start realizing basic properties of numbers and how they relate to each other, helping to solidify the fundamental rules of math that later, more complicated subjects build on.
In the above card, a student might notice that 3 is two less than 5. The card gives a visual idea of the basic arithmetic fact that 3+2 = 5. Blogger Hemant Mehta has several other examples of how ten-frame cards could be useful to students learning basic math facts in his excellent post on the check.
Of course, techniques like ten-frame cards are not intended to replace the standard number systems and algorithms we all grew up with. The Common Core standards don't explicitly mention particular teaching tools like ten-frame cards, instead just requiring students in kindergarten and the first grade to understand the basics of place value, addition, and subtraction. The standards leave the details of how to teach these concepts up to individual schools and teachers.
This is why it's a bit silly for Hermann to have written a check incorporating ten-frame cards along with X's and O's. His children aren't being taught some kind of new type of "common core numbers" as a replacement for good old base ten Hindu-Arabic numerals; they're just being exposed to alternative ways to think about those numbers to build a solid base upon which they can learn the rest of mathematics.