I was fascinated by a recent “Math Lesson” on glumbert.com called A new way to multiply. It shows how to use the intersection of lines to basically “count” your way to the solution. This was great for small digits like 1 and 2, but as I practiced the method it became apparent that it wasn’t a practical way to multiply large numbers.

So I extended the method to be able to multiply large numbers and / or large digits. For a number of reasons, I think this method is better than the standard method of multiplying. And for practical reasons, I think it is better than the line-intersection method:

  1. Unlike the standard method, you can easily check your work for errors at any step along the way.
  2. The grid is easier to visualize than the standard method, thus it may be possible to perform larger multiplications in your head.
  3. Because this method extends the line-intersection method of multiplication, it can be easily taught as a “more advanced method” once students grasp the concept of counting intersections.


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