Essential Questions: How can models be used to compute fractions with like and unlike denominators? How are models used to show how fractional parts are combined or separated? Why do we need common denominators to add or subtract fractions? How do I explain how changing the size of the whole affects the size or amount of a fraction? How can understanding fractions make your life easier? When is estimation of fractions useful? When should we overestimate or underestimate? How does estimation help us understand real world problems? Lesson Plans and Seeds Lesson Plan A.1-2: Unlike Denominators Lesson Seed A.1: Finding Equivalent Fractions Download Seeds, Plans, and Resources (zip) Unit Overview Content Emphasis By Clusters in Grade 5 Progressions from Common Core State Standards in Mathematics Send Feedback to MSDE’s Mathematics Team
Lesson Plan A.1-2: Unlike Denominators
Lesson Seed A.1: Finding Equivalent Fractions
Unit Overview
Content Emphasis By Clusters in Grade 5
Progressions from Common Core State Standards in Mathematics
Send Feedback to MSDE’s Mathematics Team
Lesson seeds are ideas that can be used to build a lesson aligned to the CCSS. Lesson seeds are not meant to be all-inclusive, nor are they substitutes for instruction. When developing lessons from these seeds, teachers must consider the needs of all learners. It is also important to build checkpoints into the lessons where appropriate formative assessment will inform a teachers instructional pacing and delivery.
Students use their understanding of fraction equivalence to generate equivalent fractions in order to add and subtract fractions with unlike denominators. They will solve word problems with unlike denominators using visual models or equation. Students need a sense of fractions to estimate mentally and assess the reasonableness of their answer.
Enduring Understandings:
At the completion of the unit on addition and subtraction of fractions with unlike denominators, the student will understand that:
Focus Standards (Listed as Examples of Opportunities for In-Depth Focus in the PARCC Content Framework document):
5.NF.A.2 When students meet this standard, they bring together the threads of fraction equivalence (grades 3–5) and addition and subtraction (grades K–4) to fully extend addition and subtraction to fractions.
Possible Student Outcomes:
The student will be able to:
Evidence of Student Learning:
Fluency Expectations and Examples of Culminating Standards:
Common Misconceptions:
Student may:
Interdisciplinary Connections:
Interdisciplinary connections fall into a number of related categories:
Sample Assessment Items: The items included in this component will be aligned to the standards in the unit and will include:
Interventions/Enrichments/PD: (Standard-specific modules that focus on student interventions/enrichments and on professional development for teachers will be included later, as available from the vendor(s) producing the modules.)
Vocabulary/Terminology/Concepts: This section of the Unit Plan is divided into two parts. Part I contains vocabulary and terminology from standards that comprise the cluster, which is the focus of this unit plan. Part II contains vocabulary and terminology from standards outside of the focus cluster. These “outside standards” provide important instructional connections to the focus cluster.
Part I – Focus Cluster Number and Operations – Fractions: Use Equivalent Fractions as a Strategy to Add and Subtract Fractions
identity property of multiplication: This is also called the multiplicative identity. The identity for multiplication is the number 1, because 1 multiplied by any number is equal to that number. m × 1 = 1 × m is equal to m. Remembering that 1 = a/a when a ≠ 0. benchmark fractions: Benchmark fractions are used for estimation. When you add 1/3 + 3/5 = 5/15 + 9/15 you get 14/15. When you estimate the addition, you would think that 1/3 is closer to 1/2 and 3/5 is closer is 1/2 so your estimated answer would be about 1. The benchmark used with fractions are 0, 1/2, 1. Also 1/3 is less than 1/2 and 3/5 is more than 1/2, so we know that 1/3 < 3/5.
Part II – Instructional Connections outside the Focus Cluster NOTE: None of the vocabulary, terminology, and concepts in this cluster are new, nor should they be particularly problematic for instruction of the related standards.
