Lesson 5

Counting On to Add with Number Lines

Est. Class Sessions: 1
X

Mathematical Standards

1.NBT.A
Extend the counting sequence. (1.NBT.A.1)
1.OA.A
Represent and solve problems involving addition and subtraction. (1.OA.A.1, 1.OA.A.2)
1.OA.C
Add and subtract within 20. (1.OA.C.5, 1.OA.C.6)
1.OA.D
Work with addition and subtraction equations. (1.OA.D.7)

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.
MP5.
Use appropriate tools strategically.
MP6.
Attend to precision.
MP8.
Look for and express regularity in repeated reasoning.

Students practice counting on from one-digit and two-digit numbers to solve addition problems within the context of using a calendar. Their work is supported by using a number line.

Content in this Lesson

  • Composing and decomposing numbers using number lines and number sentences [E1].
  • Solving addition problems using a counting-on strategy [E5].
  • Solving addition word problems using calendars and number lines [E6].
  • Representing addition situations with number sentences [E7].
  • Connecting different representations of quantities (number lines and calendars) [E4].
  • Using a calendar to measure the passage of time.
  • Connecting mathematics to real-world situations.
  • Choosing good tools to solve an addition problem [MPE2].
  • Explaining a strategy for solving an addition problem [MPE5].
  • Solving a problem another way to check for reasonabless and mistakes [MPE3, MPE4].

Daily Practice and Problems M–N

M. Counting On Using the Number Line

N. What Is Missing?

X

Materials for Students

Daily Practice and Problems Lesson Homework Assessment

Student Books

 Student Activity Book

Teacher Resources

 Teacher Guide - digital

Supplies for Student Pairs

desk number line 0–40
connecting cubes
small counters

Materials for the Teacher

Display of Number Line 0–30 (Student Activity Book) Reference
Display of It's in the Mail (Student Activity Book) Pages 83–84
Display of Math Practices (Student Activity Book) Reference
Unit 4 Assessment Record
Unit 4 Individual Assessment Record
month calendar
self-adhesive notes

Materials Preparation

Prepare Classroom Calendar. Use a large month calendar to demonstrate counting-on problems with mail delivery. Write "mailed" on three self-adhesive notes and place them on the dates 7, 15, and 20. Place self-adhesive notes over the dates 8, 16, 17, 18, 21, and 22 as shown in Figure 1.

image
Figure 1: A calendar showing mailing and delivery dates

Assessment in this Lesson

Assessment Expectation Assessed Math Practices Expectation Assessed
Sending Mail with Feedback Box
Student Activity Book
Pages 85–87
E1. 
Compose and decompose numbers 1–20 using counters, drawings, ten frames, number lines, diagrams, and number sentences.
E4. 
Connect representations of quantities (e.g., counters, pictures, symbols).
E5. 
Solve addition problems using the counting-on strategy.
E6. 
Solve addition word problems (e.g., adding to, putting together, comparing) involving two or three whole numbers whose sum is less than or equal to 30 using tools (e.g., counters, number lines, calculators, diagrams, ten frames, calendars).
E7. 
Represent addition situations with stories, drawings, diagrams, counters, number lines, and number sentences.
MPE2. 
Find a strategy. I choose good tools and an efficient strategy for solving the problem.
MPE5. 
Show my work. I show or tell how I arrived at my answer so someone else can understand my thinking.
DPP Item M
Counting On Using the Number Line
Teacher Guide - digital
E3. 
Represent quantities using a ten frame, counters, pictures, number lines, and symbols.

Vocabulary in this Lesson