Lesson 4

Doubles +1, Doubles −1

Est. Class Sessions: 1–2
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Mathematical Standards

1.OA.A
Represent and solve problems involving addition and subtraction. (1.OA.A.1, 1.OA.A.2)
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)

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.
MP7.
Look for and make use of structure.

Students categorize answers to doubles problems as even or odd. They discuss how the category of their answers changes when they add 1 to (or take away 1 from) their original answers. Students demonstrate doubles +1, and doubles −1 problems by building two-column towers made of connecting cubes. They also form number sentences based on their cube models.

Content in this Lesson

  • Representing doubles and near doubles using counters and number sentences [E1].
  • Representing addition involving doubles and near doubles using stories and drawings [E2].
  • Using doubles to solve addition problems with sums to 30 [E5].
  • Explaining solutions so that others can understand thinking [MPE5].
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Materials for Students

Daily Practice and Problems Lesson Homework Assessment

Student Books

 Student Activity Book

Teacher Resources

 Teacher Guide - digital

Supplies for Students

30 connecting cubes

Supplies for Student Pairs

clear plastic spinner or pencil and paper clip

Materials for the Teacher

Prepared sets of the Doubles Cards Master (Teacher Guide) 2–4 copies. See Materials Preparation.
Display set of the Doubles Cards Master (Teacher Guide)
Display of Math Practices (Student Activity Book) Reference
Display of Doubles, Doubles +1, Doubles −1 Recording Sheet from the Doubles, Doubles +1, Doubles −1 pages (Student Activity Book) Page 377
Display set of Number Cards 1–10 (Teacher Guide)
Display of first Even or Odd page (Student Activity Book) Page 379
Unit 12 Assessment Record
chart paper to prepare the Doubles and Near Doubles chart for display

Materials Preparation

Prepare Doubles Cards. Copy the Doubles Cards Master on heavy paper or card stock. Cut out the cards. Make enough copies so that each student will have two different cards.

Prepare Number Cards 1–10. Copy the Number Cards 1–10 Master on heavy paper or card stock. Cut out one set of cards for each pair of students.

Prepare a Display of Doubles and Near Doubles Chart. Use the Doubles and Near Doubles page in the Student Activity Book as a model to create a display version of the Doubles and Near Doubles chart on chart paper. See Figure 1.


Figure 1: A Doubles and Near Doubles table

Gather Materials for Spinners. Students can either use overlay clear spinners or use a pencil and paper clip.
See Figure 2.


Figure 2: Using a pencil and paper clip as a spinner

Assessment in this Lesson

ASSESSMENT EXPECTATION ASSESSED Math Practices Expectation Assessed
Doubles and Near Doubles
Check-In: Questions 1–3
with Feedback Box
Student Activity Book
Pages 373–374
E1.
Represent doubles, near doubles, and halves using counters, pictures, and number sentences.
E5.
Use mental math strategies and reasoning strategies (e.g., using doubles, using ten, making ten) to solve addition problems with sums between 10 and 20 and the related subtraction problems.
MPE1.
Know the problem. I read the problem carefully. I know the questions to answer and what information is important.
MPE5.
Show my work. I show or tell how I arrived at my answer so someone else can understand my thinking.
Even or Odd
Check-In: Questions 1–3 Student Activity Book
Page 380
MPE5.
Show my work. I show or tell how I arrived at my answer so someone else can understand my thinking.

Vocabulary in this Lesson