Second Grade Unit 8
Partners, Teams and Paperclips
(Add & Subtract within 1,000)
​Duration: 5 Weeks
 March 18 - April 17

Math Expressions - Unit 2:  Addition and Subtraction within 200
​Investigations -  Unit 3: Stickers, Number Strings and Story Problems
Username: Valley Elementary Test
​Password: Lilac#24
​
Operations and Algebraic Thinking
Represent and solve problems involving addition and subtraction.
CCSS.MATH.CONTENT.2.OA.A.1
Use addition and subtraction within 100 to solve one- and two-step word problems (we are focusing in within 20 for T1) 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.1

Add and subtract within 20.
CCSS.MATH.CONTENT.2.OA.B.2
Fluently add and subtract within 20 using mental strategies.2 By end of Grade 2, know from memory all sums of two one-digit numbers.

Number and Operations in Base Ten
Use place value understanding and properties of operations to add and subtract
CCSS.MATH.CONTENT.2.NBT.B.6
  • Add up to four single-digit numbers using strategies based on place value and properties of operations (in T2 this becomes four double-digit numbers)
CCSS.MATH.CONTENT.2.NBT.B.8
  • Mentally add or subtract 10 to a given number 10-90 (in T2 this becomes adding 10 or 100 to 100 - 900)
Extra California CCC NOBT Standard:
7.1 Use estimation strategies to make reasonable estimates in problem solving. CA
  • Use estimations strategies in computation and problem solving with numbers up to 100
Pacing
Key Lesson
Week 1:
​Investigation 1 - Adding Even and Odd Numbers

Dates
Session 1.1:  Partners and Teams with Two Groups? 
Materials: 
  • Connecting Cubes
  • ​Story Problems (M2/R2)
  • Student Activity Book: Pages 1-2
Main Focus
  • Characterizing even and odd numbers as those that do or do not make groups of two (partners) and two equal groups (teams)
  • Investigating what happens with partners and teams when two groups are combined.

Session 1.2:  More Partners and Teams with Two Groups
Materials:  
  • Connecting Cubes
  • Student Activity Book: Pages 4-6
  • ​Problems with Two Big Groups (M2/M5-R2/R5)
Main Focus:
  • Investigating what happens with partners and teams when two groups are combined
  • Making and testing conjectures about adding even and odd numbers

Session 1.3:  Adding Even and Odd Numbers
Materials:  
  • Connecting Cubes
  • Student Activity Book: Pages 7-14
Main Focus:
  • Finding combinations of odd and even numbers that make given numbers or determining that these combinations are not possible.
  • Making and testing conjectures about adding even and odd numbers
  • Making and justifying generalizations about adding even and odd numbers.

Session 1.4:  More Adding Even and Odd Numbers
Materials:  
  • Connecting Cubes
  • Student Activity Book: Pages: 15
Main Focus:
  • Finding combinations of odd and even numbers that make given numbers or determining that these combinations are not possible.
  • Making and testing conjectures about adding even and odd numbers
  • Making and justifying generalizations about adding even and odd numbers.
Week 2:
Remaining Addition Combinations
Session 2.1:  Plus 9 or 10 Bingo

Materials:  
  • Connecting Cubes
  • Game Materials (M10-M11/R10-R11)
  • Game Instructions and Board (M10-M11/R10-R11)
  • ​Plus 9 combination cards (M12/R12)
  • ​Student Activity Book: Pages 16-17
Main Focus:
  • Relating unknown combination s to know combinations
  • Using cubes and the number line to show how addition combinations are related
  • Developing fluency with the plus 9 and remaining combinations
Session 2.2:  Remaining Combinations

Materials:  
  • Connecting Cubes
  • Remaining Combinations Cards (M13/R13)
  • ​Student Activity Book: Pages 19-22
Main Focus:
  • Relating unknown combination s to know combinations
  • Using cubes and the number line to show how addition combinations are related
  • Developing fluency with the plus 9 and remaining combinations
Week 3:
Subtraction
Session 3.1:  Pinching Paper Clips

Materials:  
  • Connecting Cubes
  • Paper Clips
  • Pinching Paper Clips (M14-M15/R14-R15)
  • ​Sticker Book Pages (M16/R16)
  • 100 chart
  • ​Student Activity Book: Pages 23-26
Main Focus:
  • Counting a set of objects by equal groiups
  • Subtracting amounts from 100
  • Developing and achieving fluency with the plus 9 remaining combinations

Session 3.2:  Subtracting in Parts

Materials:  
  • Connecting Cubes
  • Paper Stickers (M17/R17)
  • 100 chart
  • Story Problems (M18-M21/R18-M21)
  • ​Student Activity Book: Pages 27-29
Main Focus:
  • Visualizing, retelling, and modeling the action of subtraction situation
  • Representing the action of subtraction situation using (-, +, =)
  • Developing efficient methods for subtracting and notating strategies
  • Solving subtraction problems by subtracting in parts.

Session 3.3:  Adding Up or Subtracting Back

Materials:  
  • Connecting Cubes
  • Counters such as: cubes, pennies, buttons, or beans
  • ​Student Activity Book: Pages 23-34
Main Focus:
  • Solving subtraction problems by adding up or subtracting back to find the difference
  • Developing effective methods for subtracting and notating strategies
  • Subtracting amounts from 100

Session 3.4:  Story Problems

Materials:  
  • Connecting Cubes
  • 100 chart
  • Challenge: Story Problems (M22-M23/R22-R23)
  • ​Student Activity Book: Pages 35-38
Main Focus:
  • Comparing problems in which the amount subtracted differs by 1
  • Developing efficient methods for subtracting and notating strategies
  • Developing and achieving fluency with the plus 9 and remaining combinations

Session 3.5:  Assessment: Paper Clips and Cherries (M24/R24)

Materials:  
  • Connecting Cubes
  • Counters such as: cubes, pennies, buttons, or beans
  • ​Student Activity Book: Pages 39
Main Focus:
  • Developing efficient methods for subtracting and notating strategies
Week 4:
​Addition
Session 4.1:  Strategies for Addition

Materials:  
  • Connecting Cubes
  • 100 chart
  • Paper Stickers (M16/R16) as needed
  • ​Student Activity Book: Pages 40-46
Main Focus:
  • Visualizing, retelling, and modeling the action of addition situations
  • Representing the action of addition situations notation (+, =)
  • Developing efficient methods for adding and notating strategies

Session 4.2:  Keeping One Number Whole

Materials:  
  • Connecting Cubes
  • 100 chart
  • Addition Problems: Variations (M28-M29/R28-R29)
  • ​Student Activity Book: Pages 46-51
Main Focus:
  • Adding two digit numbers by keeping one whole
  • Developing efficient methods for adding and notating strategies

Session 4.3:  Adding Tens and Ones

Materials:   Main Focus:
  • Adding 2-digit numbers by adding tens and ones
  • Developing efficient methods for adding and notating strategies

Session 4.4 : Adding 2-Digit Numbers

Materials:  
  • Connecting Cubes
  • 100 chart
  • Paper stickers
  • Addition Problems: Variation (M36-M37/R36-R37)
  • ​Challenges (M38-M39/R38-R39)
  • ​Student Activity Book: Pages 57-61
Main Focus:
  • Noticing what happens to place value when two 2-digit numbers with a sum over 100 are combined
  • Developing efficient methods for adding and notating strategies

Session 4.4 : End-of-Unit Assessment

Materials:  
  • Assessment (M41-M45/R41-R45)
  • Connecting Cubes
  • 100 chart
  • Paper stickers
  • ​Student Activity Book: Pages 62-64
Main Focus:
  • Making and justifying generalizations about adding even and odd numbers
  • Developing and achieving fluency with plus 9 and remaining combinations
  • Adding 2-digit numbers accurately and efficiently.
Week 4:
​Supplemental Unit: 8 5A.1
Session 5A.1:  Combining Stickers
Materials: 
  • Paper Stickers
  • C84/C85-C86/C87/C88(needs to be added)
  • ​100 Stickers Sheets
  • Student Activity Book: Pages 65-68
Main Focus
  • Representing 3-digit numbers using a place-value model
  • Representing a 3-digit number as hundreds, tens and ones
  • Adding two 3-digit numbers by combining hundreds, tens and ones

Session 5A.2:  Adding Hundreds, Tens, and Ones
Materials: 
  • Paper Stickers
  • C89-C90/C91-C92/C93(needs to be added)
  • Student Activity Book: Pages 69-71
Main Focus
  • Representing 3-digit numbers using a place-value model
  • Representing a 3-digit number as hundreds, tens and ones
  • Adding two 3-digit numbers by combining hundreds, tens and ones
  • Noticing what happens to the place value when two numbers are combined and there are more than 10 ones in the ones place or 10 tens in the tens place.

Session 5A.3:  Subtracting Hundreds, Tens, and Ones
Materials: 
  • C94-C95/C96/C87(needs to be added)
  • Plus or Minus 100 (needs to be added)
  • Student Activity Book: Pages 72-77
Main Focus
  • Representing 3-digit numbers using a place-value model
  • Representing a 3-digit number as hundreds, tens and ones
  • Solving a subtraction problem by keeping one number whole and subtracting the other in parts by place

Session 5A.4:  Subtracting 3-Digit Numbers
Materials: 
  • C97-C98/C99-C100(needs to be added)
  • ​More Sticker Problems
  • Fraction Practice
  • Student Activity Book: Pages 78-81
Main Focus
  • Representing 3-digit numbers using a place-value model
  • Representing a 3-digit number as hundreds, tens and ones
  • Solving a subtraction problem  by keeping one number whole and subtracting the other in parts by place

Session 5A.5:  End-of-Unit Assessment
Materials: 
  • Paper Stickers
  • Connecting Cubes
  • 100 charts
  •  Assessment C101-C106(needs to be added)
  • Assessment Checklist (C107) (needs to be added)
  • ​100 Stickers Sheets
  • Student Activity Book: Pages 82-83
Main Focus
  • Making and justifying generalizations about adding even and odd numbers
  • Developing and achieving fluency with the plus 9 and remaining combinations
  • Adding 2-Digit and 3-digit numbers accurately and efficiently.

Additional Resources