Lesson 3

Close Enough!

Est. Class Sessions: 3
X

Mathematical Standards

3.NBT.A
Use place value understanding and properties of operations to perform multi-digit arithmetic. (3.NBT.A.1, 3.NBT.A.2)

Standards for Mathematical Practice

MP1.
Make sense of problems and persevere in solving them.
MP2.
Reason quantitatively.
MP4.
Model with mathematics.
MP5.
Use appropriate tools strategically.
MP6.
Attend to precision.

Students use base-ten pieces and number lines to develop an understanding of rounding numbers to the nearest ten and hundred. They then estimate sums using strategies including rounding to benchmarks, using convenient numbers, and front end estimation to solve problems involving estimation of sums.

Content in this Lesson

  • Applying place value concepts to addition [E1].
  • Rounding to benchmark numbers [E5].
  • Estimating sums using mental math strategies, including rounding to benchmark numbers [E5].
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Materials for Students

Daily Practice and Problems Lesson Homework Assessment

Student Books

 Student Guide
Student Activity Book

Teacher Resources

 Teacher Guide - digital

Supplies for Student Pairs

base-ten pieces: 14 flats, 30 skinnies, and 50 bits
desk number line 0–100
tape

Materials for Teachers

Display of Rounding Numbers, Questions 1–2 (Student Activity Book) Page 181
Unit 6 Assessment Record
Math Facts Class Record
class number line 0–130

Assessment in this Lesson

Assessment Expectation Assessed

Close Enough!
Check-In: Questions 5–7
Student Guide
Page 134
E5.
Estimate sums using mental math strategies (e.g., rounding using benchmarks, using convenient numbers, composing and decomposing numbers, counting on).

Places Please
Teacher Guide - digital
E1.
Use and apply place value concepts to make connections among representations of numbers to the thousands using base-ten pieces, number lines, expanded form, and standard form.
E5.
Estimate sums using mental math strategies (e.g., rounding using benchmarks, using convenient numbers, composing and decomposing numbers, counting on).

DPP Item K
Subtraction Practice
Teacher Guide - digital
E6.
Use mental math strategies to subtract for the facts in all groups.

DPP Item O
Fact Families
Teacher Guide - digital
E7.
Determine the unknown number in an addition or subtraction sentence relating three whole numbers for the facts in all groups.