Introduction

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Base ten is a tricky concept in early math. Our number system is abstract and requires critical thinking. Consider the following:

  • A group of ten is simultaneously ten ones and one ten.
    (It’s both at the same time!)
    This idea is called “unitizing.”

  • Numbers hold a different value depending on their order. All the numbers below, for example, are written with a 1 and a 2 but have very different meaning. (These numbers change meaning when they change places!)
    This idea is called “positional notation.”

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  • The number zero holds new meaning when writing multi-digit numerals. It makes all the difference between 1, 10, and 100. (More zeros make for a bigger number!)

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See? This is complex stuff!

Understanding base ten requires very strong Number Sense not only of numbers 1 through 9, but of zero, too.

In this section, you’ll see some examples of how students’ understanding of base ten evolves, consider the best hands-on materials to support these big ideas, and revisit a PWN favorite math tool: the rekenrek.

Click the blue button below to dig in!