CKMath Unit 3: Extending Operations to Fractions
Focus:
In this unit, students deepen their understanding of how fractions can be composed and decomposed, and learn about operations on fractions. Students multiply fractions by whole numbers, add and subtract fractions with the same denominator, and add tenths and hundredths. They rely on familiar concepts and representations to do so. For instance, students had represented multiplication on a tape diagram, with equal-size groups and a whole number in each group. They use a tape diagram that shows a fraction in each group. In earlier grades, students used number lines to represent addition and subtraction of whole numbers. Here, they use number lines to represent the decomposition of fractions into sums, and to reason about addition and subtraction of fractions with the same denominator, including mixed numbers. Students then apply these skills in the context of measurement and data. They analyze line plots showing fractional lengths and find sums and differences to answer questions about the data. Lastly, students use fraction equivalence to find sums of tenths and hundredths. For instance, to find 3/10+15/100 , they reason that 3/10 is equivalent to 30/100, so the sum is 30/100+15/100, which is 45/100.
Number of Lessons: 18 and 2 optional
Instruction Time:
Approximately 60 minutes
(Please note that each lesson is designed for one instructional block, and may be divided into shorter or longer segments based on teacher pacing and student needs.)
