This lesson is optional because it goes beyond the depth of understanding required to address the standards. The standards do not require students to create their own story problems. This lesson does provide students the opportunity to apply skills of mathematical modeling.

In previous lessons, students represented and solved a variety of Add To, Result Unknown and Take From, Result Unknown story problems. In this optional lesson, students apply what they’ve learned about story problems throughout the section to tell a story problem that includes an action and a question. Students share and solve story problems with their partner. When students change the story to change the action and the mathematical operation of the problem, they understand how addition and subtraction model actions in the real world (MP2, MP4).