Fact families
http://illuminations.nctm.org/LessonDetail.aspx?ID=L41
A lesson plan for grades 1–2 Mathematics
In this lesson, the fifth of a six-part unit from Illuminations, students use books and connecting cubes to explore the relationship of addition to subtraction. Students search for related addition and subtraction facts for a given number using a virtual or actual calculator to find differences. They also investigate fact families when one addend is 0 as well as when the addends are the same.
North Carolina Curriculum Alignment
Mathematics (2004)
Grade 1
- Goal 1: Number and Operations - The learner will read, write, and model whole numbers through 99 and compute with whole numbers.
- Objective 1.03: Develop fluency with single-digit addition and corresponding differences using strategies such as modeling, composing and decomposing quantities, using doubles, and making tens.
- Objective 1.04: Create, model, and solve problems that use addition, subtraction, and fair shares (between two or three).
Grade 2
- Goal 1: Number and Operations - The learner will read, write, model, and compute with whole numbers through 999.
- Objective 1.03: Create, model, and solve problems that involve addition, subtraction, equal grouping, and division into halves, thirds, and fourths (record in fraction form).
- Objective 1.05: Create and solve problems using strategies such as modeling, composing and decomposing quantities, using doubles, and making tens and hundreds.
