Grade2: Module 4 – Parent Letter
What’s It All About?
Module 4 focuses on building fluency in two-digit addition and subtraction and
applying that fluency to one- and two-step word problems of varying types within
100. Students will work on variety of problem types, including the more complex
comparison problems.
New or Recently Introduced Terms:
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Equation: an equation is like a statement "this equals that"; e.g., 3 + 4 = 7
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Minuend: the first number in a subtraction problem
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Subtrahend: the number being subtracted in a subtraction problem
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Place value chart
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Place value or number disk
Familiar Terms and Symbols
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Addend
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Addition
Difference
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Place value: the unit value of each digit in a given number
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Subtraction Units of ones, tens, hundreds, thousands: referring to place
value; 10 ones is the same as 1 unit of ten
Topic A :
Students relate 10 more and 10 less and 1 more and 1 less to addition and
subtraction. They record the addition and subtraction of multiples of 10 using
arrow notation.
Topic B:
Students will apply their understanding of place value strategies to move from
horizontal to vertical addition sentences. Their understanding of vertical addition
starts with work with number disks, moving to place value chart drawings, and
ending with the number sentence.
Topic C:
Students will apply their understanding of place value strategies to the subtraction
algorithm. They will use number disks on a place value chart to subtract like units
(e.g., 47 – 31 is 4 tens – 3 tens and 6 ones – 1 one).
Students continue dot drawings and decomposing tens to subtract two-digit
numbers.
Mid-Module Assessment:
Show mental strategies when adding and subtracting two-digit numbers.
Solve addition and subtraction problems using the place value model.
Identify number sentences as correct or incorrect and show how you know.
Use words, pictures and numbers to solve word problems involving two-digits.
Topic D:
Students will use place value strategies to add and subtract three-digit numbers.
Topic E:
Students will use number bonds to break apart three-digit minuends and subtract
from the hundred.
Topic F:
Students think about and discuss the multiple strategies they have learned to
represent and solve addition and subtraction problems. They share their reasoning
as they link their drawings to two written methods, and discuss the similarities,
and differences, and which approach works best.
**End-of-Module Assessment:
Add and subtract two and three-digit numbers using mental math.
Add up to four two and three-digit numbers using strategies based on place
value and properties of operations.
o use models or drawings and strategies based on place value
o explain why solutions are correct or incorrect
Find missing numbers to make given statements true. Show mental math
strategy.
Use words, pictures and numbers to solve word problems involving twodigits.