Lesson 13

The purpose of this lesson is for students to solve Take From problems, with unknowns in all positions, in a way that makes sense to them.

In previous units, students solved Take From problems with the Result or Change unknown. In this lesson, students solve a new problem type, Take From, Start Unknown. This type of problem is often challenging for students as the language signifies subtraction, but you must add to solve the problem. Students consider how a drawing represents different Take From story problems. Students are not required to master this type of problem until grade 2.

• Create a poster of the unlabeled diagram shown three times: 

  

  

In grade 2, students are introduced to tape diagrams as a tool for making sense of story problems. How does the work of this lesson lay the foundation for understanding tape diagrams? How will the tape diagrams used in grade 2 be different than the diagram students analyzed today?