Lesson 4

Addition with Triangle Flash Cards

Est. Class Sessions: 1
X

Mathematical Standards

2.OA.A
Represent and solve problems involving addition and subtraction. (2.OA.A.1)
2.OA.B
Add and subtract within 20. (2.OA.B.2)
2.MD.B
Relate addition and subtraction to length. (2.MD.B.6)
2.MD.C
Work with time and money. (2.MD.C.8)

Standards for Mathematical Practice

MP2.
Reason quantitatively.
MP4.
Model with mathematics.
MP5.
Use appropriate tools strategically.
MP6.
Attend to precision.

This lesson introduces a yearlong, systematic, strategies-based approach for developing fluency with the addition and subtraction facts. This lesson introduces the use of Triangle Flash Cards to practice the addition facts and begins work with Groups A and B. Students also revisit the properties of adding zero and fact families.

Content in this Lesson

  • Practicing the addition facts using Triangle Flash Cards.
  • Finding fact families.
  • Demonstrating fluency with the addition facts with sums to ten in Groups A–B [E7].
  • Determining the unknown number in an addition or subtraction sentence relating three whole numbers for the facts in Groups A–B [E8].
  • Representing addition and subtraction situations using number sentences and stories [E1].
  • Using addition and subtraction to solve word problems involving join, separate/take away, part-whole, and compare [E3].
  • Using counting strategies and the properties of zero to solve addition facts.
  • Solving addition problems and explaining reasoning.

Daily Practice and Problems K–L

K. Coin Jar 2

L. School Supplies

X

Materials for Students

Daily Practice and Problems Lesson Homework Assessment

Student Book

 Student Activity Book

Teacher Resources

 Teacher Guide - digital
  • Triangle Flash Cards: Groups A–B
  • Triangle Flash Cards: Groups A–B

Supplies for Students

scissors
envelope or resealable plastic bag
paper clip

Materials for the Teacher

Display of Large Triangle Flash Card Master (Teacher Guide)
Unit 1 Assessment Record
Math Facts Class Record
10 small buttons or counters
chart paper
Counting Strategies and Reasoning Strategies charts from Lesson 3

Materials Preparation

Triangle Flash Cards. Prepare copies of the Triangle Flash Cards on heavier paper or card stock. Have students cut apart each set and store them in an envelope. Provide each student with two sets, one to use at school and one to take home. Students will need these cards on an ongoing basis.

Assessment in this Lesson

Assessment Expectation Assessed
Fact Families with Addition Triangles
with Feedback Box
Student Activity Book
Pages 15–18
E1.
Represent addition and subtraction situations using multiple representations (e.g., stories, drawings, counters, number sentences, number lines, diagrams, ten frames).
E7.
Demonstrate fluency with the addition facts in Group A (0 + 1, 1 + 1, 2 + 1, 3 + 1, 0 + 2, 2 + 2, 3 + 2, 4 + 2) and Group B (3 + 0, 4 + 0, 4 + 1, 5 + 1, 6 + 1, 5 + 2, 6 + 2, 5 + 3, 7 + 1, 1 + 8).
E8.
Determine the unknown number in an addition or subtraction sentence relating three whole numbers for the facts in Groups A and B.
Self-Assessment with
Triangle Flash Cards
Teacher Guide - digital
E7.
Demonstrate fluency with the addition facts in Group A (0 + 1, 1 + 1, 2 + 1, 3 + 1, 0 + 2, 2 + 2, 3 + 2, 4 + 2) and Group B (3 + 0, 4 + 0, 4 + 1, 5 + 1, 6 + 1, 5 + 2, 6 + 2, 5 + 3, 7 + 1, 1 + 8).

Vocabulary in this Lesson