Topic 11 Week 27 Feb. 26 , 2019

Topic 11 MAFS.1.NBT.3.6 (DOK 2) Subtract multiples of 10 in the range 10-90 from multiples of 10 in the range 10-90 (positive or zero differences), using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used. [Conceptual Understanding] · Identify the value of each digit of a number within 100. · Use concrete models or drawings to subtract multiplives of 10 in the range of 10-90 from multiples of 10 in the range of 10-90 (positive or zero differences). · Choose an appropriate strategy (based on place value, properties of operations, and/or the relationships between addition and subtraction) for solving subtraction problems with multiples of 10. · Relate the chosen strategy to a written method (equation) and explain the reasoning used

I Do! How can I solve 70-40 using an open number line? I will use the open number line below to show you. This is one tool that we can use. ____ - ____ = _____

We Do! Mrs. Vales has 80 marshmallows. She gives 40 to her students. How many does she have left?

They Do! They DO: Tina has 90 pride bucks. She uses 70 of them to buy prizes. How many pride bucks does she have left?

You Do! There are 30 flowers in my garden. My sister picked 20. How many flowers are left?

You Do! Wilson has 40 books. He reads 10. How many books does Wilson have left? You may use any strategy you want. Which did you choose? Why? ____________________________________________________________________ _____________________________________________________________________