Lesson 3

Comparing: How Many More

Est. Class Sessions: 2
X

Mathematical Standards

1.OA.A
Represent and solve problems involving addition and subtraction. (1.OA.A.1)
1.OA.B
Understand and apply properties of operations and the relationship between addition and subtraction. (1.OA.B.3)
1.OA.C
Add and subtract within 20. (1.OA.C.6)
1.OA.D
Work with addition and subtraction equations. (1.OA.D.8)

Standards for Mathematical Practice

MP1.
Make sense of problems and persevere in
solving them.
MP2.
Reason quantitatively..
MP3.
Construct viable arguments and critique the reasoning of others.
MP4.
Model with mathematics.
MP6.
Attend to precision.

Students use addition strategies to solve problems that involve a comparative situation. They use the At the Circus page to make comparisons between two sets of objects and determine how many more there are of one than the other.

Content in this Lesson

  • Comparing two sets of objects.
  • Finding the unknown whole number in an addition or subtraction equation relating three whole numbers [E5].
  • Solving comparative word problems involving two whole numbers whose answer is less than or equal to 10 [E6].
  • Adding and subtracting within 10 using invented, counting, and reasoning strategies [E7].
  • Representing comparative subtraction using stories, drawings, counters, number sentences, number lines, and ten frames [E2].
  • Knowing what is important to solve a problem [MPE1].
  • Finding addition strategies to solve subtraction problems [MPE2].
  • Solving problems a second way to check work [MPE4].
  • Explaining solutions so that others can understand thinking [MPE5].
X

Materials for Students

Daily Practice and Problems Lesson Homework Assessment

Student Book

 Student Activity Book

Teacher Resources

 Teacher Guide - digital

Supplies for Student Pairs

10 connecting cubes
desk number lines 0–40

Materials for the Teacher

Display of At the Circus (Adventure Book) (Student Activity Book) Page 129
Display of Math Practices Reference
Unit 6 Assessment Record
Math Facts Class Record
chart paper
red and blue connecting cubes
Addition Strategies chart from Lesson 1

Materials Preparation

Prepare a Chart. Make a chart entitled "How Many More at the Circus" on chart paper. Write the cloze sentence "How many more _______ than _______ ?" several times on the chart as shown in Figure 1. Leave space for work under
the first two.

Figure 1: A chart for listing comparison situations from the At the Circus page

Assessment in this Lesson

Assessment Expectation Assessed Math Practices Expectation Assessed
How Many More at the Circus
with Feedback Box
Student Activity Book
Pages
131–134
E2.
Represent addition and subtraction using stories, drawings, diagrams, counters, number sentences, number lines, or ten frames.
E5.
Find the unknown whole number in an addition or subtraction equation relating three whole numbers.
E6.
Solve word problems (e.g., separate/take away, part-whole, compare) involving two whole numbers whose answer is less than or equal to 10.
E7.
Add and subtract within 10 using invented, counting (e.g., counting on, counting up, counting back), and reasoning (e.g., making ten, using ten, using doubles) strategies.
MPE1.
Know the problem. I read the problem carefully. I know the questions to answer and what information is important.
MPE2.
Find a strategy. I choose good tools and an efficient strategy for solving the problem.
MPE4.
Check my calculations. If I make mistakes, I correct them.
MPE5.
Show my work. I show or tell how I arrived at my answer so someone else can understand my thinking
DPP Item G
Missing Numbers Teacher Guide - digital
E8.
Use mental math strategies to add (e.g., direct modeling, counting strategies, reasoning from known facts) for the facts in Groups A and B.

Vocabulary in this Lesson