This lesson is focused on 1.OA.C.6, using the relationship between addition and subtraction, and 1.OA.B.3, applying properties of operations as strategies to add and subtract. In this lesson, students learn about fact families using dominoes. Students work to create two addition and two subtraction sentences that are related, using the same three numbers. Core Actions 2 and 3 are strongly exhibited in this lesson.
Fact Families (Doetch/Falk)Download
To begin the lesson, the teachers lead their students through a mental math exercise. First, students are given time to solve the problem on their own. Then, the teacher calls on several students to share their solution and the strategies that they used to find their answers. The students are also given an opportunity to share their strategies with their partners and to be active listeners.
Here, students are engaging with the second mental math problem of the lesson. The teacher encourages students to begin by using their brain. If they are stuck, they may choose a tool to help them solve the problem. Students are observed retrieving tools to support their thinking. The teachers are circulating and asking students to share their thinking. Again, students have an opportunity to share their ideas with a partner.
After giving the students time to work through the second mental math problem, the teachers bring the class back together to share the different strategies they used to solve the problem. Students have opportunities to share a variety of strategies as well as explain their thinking and re-voice the thinking of their classmates.
After the students have ample time to work through a math problem, the teacher notices that some students have not found a strategy to solve the problem. She calls on a couple of students to share the strategy they used. After each student shares a strategy, another student re-voices what the first student just shared with their classmates.Students are developing and demonstrating their conceptual understanding of the relationship between addition and subtraction.
The second part of the lesson is learning about fact families and recognizing the relationship between addition and subtraction. The teacher shows an image of a domino with 3 and 6 dots on it. He asks, "What's the missing number for this domino?" A students responds with 12 as the missing number. The students comes up to the board to recheck her counting. Students correctly identify the numbers as 9, 6, and 3. Then the students are challenged to write an addition problem using all three numbers. This is an example for students to practice with before engaging in independent work.
The teacher summarizes the lesson by both reviewing the skill they learned and also reinforcing the lesson's vocabulary. He engages students in the discussion by having one student explain what a fact family is. Then students share what a fact family is with his/her partner. The teacher looks back at the lesson objectives, as well.