Lesson objective: Understand that when the place value extends to thousandths, the structure does not change.

Students bring prior knowledge of decimal notation from 4.NBT.C.6. This prior knowledge is extended to the new concept as students discover that hundredths can be split into smaller units. A conceptual challenge students may encounter is that a flat is always assigned the value of “one”, when in reality, the blocks representing the value of “one” may change.

The concept is developed through work with base ten blocks, number line, and the place value chart, which allow for a visual demonstration and support the idea of consistency in the structure of the base ten number system.

This work helps students deepen their understanding of equivalence as they discover that ten thousandths are equivalent to one hundredth.

Students engage in Mathematical Practice 7 (Look for and make use of structure) as they analyze the consistent structure of a place value system through visual representations.

**Key vocabulary:**

- decimal
- digit
- hundredths
- tenths
- thousandths
- value of a digit

**Special materials needed:**

- base ten blocks
- number line
- place value chart