Lesson objective: Understand that the meaning of division is the same when used with decimals as whole numbers.

Students bring prior knowledge of division of whole digit numbers from 4.NBT.5. and 5.NBT.5. This prior knowledge is extended to decimal numbers as students use division to find unknown quantities (number of cookies). A conceptual challenge students may encounter is arriving at a quotient that is greater than the divisor.

The concept is developed through work with money and flats , which allows students to visually see the whole number being separated into smaller parts. They also are introduced to the compensation method of division.

This work helps students deepen their understanding of operations because the relationship remains the same between divisor and quotient for decimal numbers as well as whole numbers.

Students engage in Mathematical Practice 7 (Look for and make use of structure) as they deepen and broaden their understanding of place value and the base 10 number system beyond whole numbers to decimals by extending their knowledge of decomposing larger units into smaller units. They also make the connection that if both the divisor and the dividend are multiplied by the same power of ten, then the value of the quotient is unchanged.

**Key vocabulary:**

- decompose
- divisor
- dividend
- compensate
- quotient

**Special materials needed:**