Author:
DAWNE COKER
Subject:
Mathematics
Material Type:
Reference Material, Teaching/Learning Strategy
Level:
Lower Primary
Tags:
  • 2-digit
  • 3-digit
  • Add
  • Adding
  • Addition
  • Approach
  • Break Apart
  • Cl4Additional
  • Cl5Additional
  • Cluster 4
  • Cluster 5
  • Compose
  • Decompose
  • Number Line
  • Place Value
  • Strategy
  • Subtract
  • Subtraction
  • Tool
  • Unit 4
  • Unit 5
  • License:
    Creative Commons Attribution
    Language:
    English
    Media Formats:
    Downloadable docs

    Education Standards

    T4T Strategies for Adding & Subtracting 3-Digit Numbers

    T4T Strategies for Adding & Subtracting 3-Digit Numbers

    Overview

    This resoruce is from Tools4NCTeachers.

    Second graders use a variety of strategies based on place value and number relationships to add and subtract multi-digit numbers.  The first attachment in this resource outlines strategies for adding 3-digit numbers, and the second attachment outlines strategies for subtracting 3-digit numbers.

    Second graders are not taught the standard algorithm.

     

    Here is a sample of this resource. Click the attachments to access the fully-formatted files.

    Strategies for Solving Three-Digit Addition Problems

    These are examples of strategies students could use to solve 3-digit problems.  These are not the only strategies students could use.

     

    Counting Up

    322 + 249                                                                    322 + __________ = 571

    322 + 200 = 522                                                          

    522 + 40 = 562                                                             322 + 8 = 330

    562 + 9 = 571                                                              330 + 70 = 400 (or the student could count up by 7 tens)

                                                                                        400 + 100 = 500

    500 + 71 = 571

     

     

     

     
     
     

     

     

     

     

     

     

     

    322

    422                 522            532 542 552 562    563, 564, 565, …… 571

     

     

     

    Place Value

    322 + 249                                                                                                                      322

    300 + 200 = 500                                                                                                           +249

    20 + 40 = 60                                                                                                                  500

    2 + 9 = 11                                                                                                                       60

    500 + 60 + 11 = 571                                                                                                     +  11

       57