The property of exponents, is equivalent to , might present an obstacle in the associated Algebra 1 lesson. The purpose of the Warm-up is to revisit writing equivalent expressions using this property. When students realize that they can use properties to rewrite expressions, they are noticing and making use of structure (MP7). Additionally, this lesson introduces that terminology like “quarterly” means “four times per year,” which students will be expected to interpret correctly for the next several lessons. In the activity “How Many Times per Year?” students perform a few numerical computations and then generalize by writing an expression, which is an example of expressing regularity in repeated reasoning (MP8).