This lesson is optional because it does not address any new mathematical content standards. This lesson provides students with an opportunity to apply precursor skills of mathematical modeling (MP4). In previous lessons, students multiplied fractions and divided whole numbers and unit fractions. In this lesson, students work with the context of recipes to apply what they’ve learned about multiplying fractions and dividing whole numbers and unit fractions. Students learn about the type of information given in recipes and generate mathematical questions that could be asked about a recipe. Then they solve a problem in which limited measuring tools are available to measure out the ingredients of a recipe. Throughout the problem solving process, students have to identify relationships between the measuring tools they have available and the amounts in the recipe.

If you were to teach this lesson over again, what activity would you redo? How would your proposed changes support student learning?