Lesson objective: Understand that decimals with different numbers of digits can be compared.

Students bring prior knowledge of comparing mulit-digit numbers from 4.NBT.A.2. This prior knowledge is extended to decimals as students compare decimals with different numbers of digits. A conceptual challenge students may encounter is how to apply their understanding of place value as they use placeholders and number lines to compare decimals with different numbers of digits to the right of the decimal point.

The concept is developed through work with a place value chart, which will help students understand the relationship between place values and the role of placeholders. Number lines will also help students better understand the relationship between different numbers.

This work helps students deepen their understanding of number because it will help students better understand the role of place value as they compare numbers with different numbers of digits.

Students engage in Mathematical Practice 7 (Look for and make use of structure) as they use place value charts, placeholders, and number lines to compare decimals with different numbers of digits.

**Key vocabulary:**

- compare
- decimal
- equal to
- equivalent
- greater than
- hundredths
- less than
- placeholder
- place value
- tenths
- thousandths

**Special materials needed:**

- scratch paper and number lines as needed