This lesson focuses on 3.OA.A.3 - using multiplication strategies to solve a word problem (note that the required computation is slightly beyond the scope of the standard: 17 x 6 is not within 100). Students persevere in solving the word problem using multiple strategies, choosing appropriate tools, explaining their thinking, and checking their work. Core Action 3 is strongly exhibited in this partial lesson.
Perseverance in Solving Multiplication Word Problems (Penney)Download
This lesson prompts students to apply their understanding of various multiplication strategies to solve a given word problem, appropriately targeting the application aspect of rigor.
Throughout the lesson, the teacher makes notes on a clipboard about the strategies students are using to gauge their levels of understanding (based on the CCSS Progressions). The teacher is checking for understanding of the problem, as well as the depth of student understanding, in order to make decisions about instruction moving forward.
The teacher poses a word problem to the class, and then asks students to solve the problem using different strategies. Students work independently to solve this problem for the next 30 minutes, as the teacher monitors student work.
Students are using a variety of math tools and strategies to solve the given problem. These tools and strategies are based on individual selections, rather than having a tool or strategy prescribed by the teacher.
Throughout the students' work time, the teacher confers with individual students, questioning them about their strategy choices and thinking. Her questions require students to justify their work (with varied levels of support) and make revisions when needed.
The student shares her solution strategy for the word problem, explaining her mathematical thinking. As she comes to her answer, the teacher asks her to label her answer, encouraging the student to "go back to the question to figure out what they're asking us." As the student determines the correct label, the teacher thanks her for using precision.
The teacher looks at the student's work and then asks him to explain his strategy choice and thinking. As he explains his thinking, she helps him talk through his work and provides some clarification about his computation. At the end of their conversation, the student explains that he is going to check his work with another strategy, and she suggests that he may want to rethink some of his work.
The teacher asks: "Tell me how these math tools helped you solve the problem." The student is able to explain his thinking, both in how the tool represents the problem and how the tool helps the student perform the required calculation. The teacher asks clarifying questions to ensure the student's thinking is clear and accurate.
The students were allowed to select a tool to solve the problem. The teacher questions this student about his choice, prompting him to explain how he used the tool strategically to help him represent and solve the problem.