Addition Word Problems Sums Within 20 | Change Unknown |Think Boards and Posters


The word problems in this resource focus on addition sums to 20 and are all “Change Unknown” problems. Change Unknown addition problems are problems that require the student to find how many more need to be added to a number to arrive at a given total. The problems are presented on Think Boards, great graphic organizers that outline different strategies that may be used to solve the problem.

As a result of using these think boards, your students will be armed with the knowledge and experience of using a variety of strategies and they will start to make their own decisions as to the most appropriate strategy for them to use at any one time.

You will find:

  • 5 posters showing the strategies used on the Think Boards for you to print and display in the classroom
  • 10 Think Boards – (2 per page) “Change Unknown” addition word problems – numbers to 20
  • 4 Think Boards – the number sentence (equation) is provided and students must create the number story
  • 2 Assessment Worksheets – each with 5 word problems.

Other teachers have said:

⭐️⭐️⭐️⭐️⭐️  “I find that teaching word problems takes extra time and practice, especially when the work problems involve missing addends. These graphic organizers and additional posters to help the students “think” their way through the problems provide excellent engaging practice. Laminating them with thick laminate ensures you can use a dry-erase marker and continue practicing!” Stephanie S.

⭐️⭐️⭐️⭐️⭐️  “My students found the posters extremely helpful when picking a strategy to solve word problems. ” Lisa M.

⭐️⭐️⭐️⭐️⭐️ “These colorful posters have been game changers for my math strugglers!” Brittney S.

Terms of Use:

Copyright: Bee Happy Teaching

This resource is for one classroom use only. It is bound by copyright laws and redistributing, editing, selling or posting this item (or any part thereof) on the internet are all strictly prohibited without first gaining permission from the author. Violations are subject to the penalties of the Digital Millennium Copyright Act.

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Sold By: Bee Happy Teaching

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16.5 MB

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PDF, Assessment, Worksheets

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