+Basic Facts -

Learning the Facts

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.

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

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.

Students will learn these addition and subtraction facts through frequent and repeated use. In school, we will be playing lots of games that help students learn particular groups of facts. Students will also play some of these games for homework. We’ll also be using Fact Cards like the one below.

Students use these cards to practice their facts and sort them into two envelopes—“Facts I Know” and “Facts I Am Still Working On.” We think a lot about ways to remember the facts that students find difficult. For example, your child might write, “Think 5 + 5 + 3” as a clue for solving 5 + 8.

In addition to using the facts frequently, students will focus on the numbers and relationships involved. That way, if students forget a fact, they can still solve the problem quickly and efficiently. For example, students might use the following strategies:

• • • • “8 + 5 is the same as 8 + 2, which is 10, and 3 more, which is 13.”

      • “7 + 9 is like 7 + 10, just one less. So it’s 16.”