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Learning the Facts

Dear Family,

To be able to add and subtract well, students need to become fluent with addition and subtraction within 20. In Grade 2, students learn their addition and subtraction facts over the course of the year, and fluency is expected by the end of the year. In this first number unit, students will be working with the following sets of combinations.

Fact Cards: Set 1

  • Make 10 Facts: All of the combinations of 10 made with two numbers, such as 8 + 2 and 4 + 6

  • Plus 1 Facts: Any number plus one (5 + 1), or 1 plus any number (1 + 8)

  • Plus 2 Facts: Any number plus two (3 + 2), or 2 plus any number (2 + 7)

  • Doubles Facts: Any number plus itself (5 + 5, 9 + 9)

  • • A few facts with sums less than 10 that do not fall into the above categories

Fact Cards: Set 2

These facts include the related subtraction facts for each of the above categories: the 10 Minus facts, the Minus 1 Facts, the Minus 2 Facts, and problems like 10 − 5 and 18 − 9, as well as a few that do not fall into the above categories.

Students will work on other sets of addition and subtraction facts—Plus 10 and Minus 10 Facts, Plus 9 and Minus 9 Facts, and facts that are “near” Doubles (e.g. 5 + 6 or 11 − 6)—in later units. Students are expected to be fluent with all of these facts by the end of Grade 2.


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Table of Contents

Investigations 3 in Number, Data, and Space®, Student Activity Book Unit 1 Coins, Number Strings, and Story Problems Unit 2 Attributes of Shapes and Parts of a Whole Unit 3 How Many Stickers? How Many Cents? Unit 4 Pockets, Teeth, and Guess My Rule Unit 5 How Many Tens? How Many Hundreds? Unit 6 How Far Can You Jump? Unit 7 Partners, Teams, and Other Groups Unit 8 Enough for the Class? Enough for the Grade?