Lesson objective: Understand we can make multiplicative comparisons of very large and very small numbers when those numbers are written in scientific notation.

Students bring prior knowledge of place value and powers of ten from 5.NBT.A.1 and 5.NBT.A.2. This prior knowledge is extended to numbers written in scientific notation as students make multiplicative comparisons of cell phone data usage. A conceptual challenge students may encounter is understanding how the coefficient and the powers of ten are useful in making comparisons between numbers written as powers of ten.

The concept is developed through comparing the coefficients and comparing the powers of ten. Comparing the powers of ten supports work with place value.

This work helps students deepen their understanding of equivalence because students are using an equivalent form of numbers to make comparisons. * *

Students engage in Mathematical Practice 6 (Attend to precision) as they use multiplication to compare numbers written as powers of 10. Students must be precise in their calculations, giving special attention to how the powers of ten relate to one another.

**Key vocabulary:**

- base
- coefficient
- exponent
- power