Essential Questions:
Unit 3 instructional time is focused on these power standards:
2.NBT.B.6 Add up to four twodigit numbers using strategies based on place value and properties of operations.
2.NBT.B.7 Add and subtract within 1000, 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. Understand that in adding or subtracting three digit numbers, one adds or subtracts hundreds and hundreds, tens and tens, ones and ones; and sometimes it is necessary to compose or decompose tens or hundreds.
2.NBT.B.9 Explain why addition and subtraction strategies work, using place value and the properties of operations.
2.OA.A.1 Use addition and subtraction within 100 to solve one and twostep word problems involving situations of adding to, taking from, putting together, taking apart, and comparing, with unknowns in all positions, e.g., by using drawings and equations with a symbol for the unknown number to represent the problem. SAMPLE assessment items for 2.OA.A1
2.MD.C.8 Solve word problems involving dollar bills, quarters, dimes, nickels, and pennies, using money symbols appropriately.
Unit 3 instruction is supported by these standards:
2.OA.B.2 Fluently add and subtract within 20 using mental strategies. By end of Grade 2, know from memory all sums of two onedigit numbers.
2.NBT.B.5 Fluently add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction.
2.NBT.B.8 Mentally add 10 or 100 to a given number 100–900, and mentally subtract 10 or 100 from a given number 100–900.
2.MD.B.6 Represent whole numbers as lengths from 0 on a number line diagram with equally spaced points corresponding to the numbers 0, 1, 2, ..., and represent wholenumber sums and differences within 100 on a number line diagram.3
 How would you know what size cake you need to buy for your birthday party?
 If you have 50 people in your party, how much candy do you need for the pinata?
 We will use addition and subtraction strategies to help us calculate the size of the cake we will need.
 Some strategies I can use to help me calculate the amount of candy for the pinata are doubles, doubles plus one, one more/one less, and making 10 to add 9.
Unit 3 instructional time is focused on these power standards:
2.NBT.B.6 Add up to four twodigit numbers using strategies based on place value and properties of operations.
2.NBT.B.7 Add and subtract within 1000, 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. Understand that in adding or subtracting three digit numbers, one adds or subtracts hundreds and hundreds, tens and tens, ones and ones; and sometimes it is necessary to compose or decompose tens or hundreds.
2.NBT.B.9 Explain why addition and subtraction strategies work, using place value and the properties of operations.
2.OA.A.1 Use addition and subtraction within 100 to solve one and twostep word problems involving situations of adding to, taking from, putting together, taking apart, and comparing, with unknowns in all positions, e.g., by using drawings and equations with a symbol for the unknown number to represent the problem. SAMPLE assessment items for 2.OA.A1
2.MD.C.8 Solve word problems involving dollar bills, quarters, dimes, nickels, and pennies, using money symbols appropriately.
Unit 3 instruction is supported by these standards:
2.OA.B.2 Fluently add and subtract within 20 using mental strategies. By end of Grade 2, know from memory all sums of two onedigit numbers.
2.NBT.B.5 Fluently add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction.
2.NBT.B.8 Mentally add 10 or 100 to a given number 100–900, and mentally subtract 10 or 100 from a given number 100–900.
2.MD.B.6 Represent whole numbers as lengths from 0 on a number line diagram with equally spaced points corresponding to the numbers 0, 1, 2, ..., and represent wholenumber sums and differences within 100 on a number line diagram.3
Topic 2: Strategies for two digit subtraction (10 Day(s)

SubtractingMultiple Methods
Mental Subtraction Strategies Greg Tang Two Digit Subtraction Make Ten Greg Tang Multidigit Subtraction Make Hundred Greg Tang Partial Differences Greg Tang 3 by 2 Subtraction Make Hundred Greg Tang Multidigit Subtraction Make Two Hundred Base Ten Binder (yellow) pgs 9398 Brain Pop Jr.Subtracting without Regrouping 
Money: Using Addition and Subtraction Strategies (5 days)

Going to the StoreMaking Change
Counting Money & Making Change Making change by Adding Up Learnzillion video Grocery Store Mathpg 95 Georgia Unit 3 Solving Money Word Problems Using Base Ten BlocksLearnzillion video Solving Money Word Problems by Drawing PicturesLearnzillion video I Have Who Has Money Game Read Aloud Tightwad Todd (available in math classroom resourcesstudents act out during reading with manipulatives or whiteboards) 