Lesson Plan

Explain that any fraction a/b (with a > 1) is the sum of a copies of the unit fraction 1/b, and demonstrate this with a visual fraction model

Decompose a fraction into a sum of fractions with the same denominator in more than one way, recording each decomposition as an equation

Add and subtract fractions with like denominators by joining or separating parts that refer to the same whole

Add and subtract mixed numbers with like denominators using either conversion to improper fractions or separation into whole-number and fractional parts

Solve word problems involving addition and subtraction of fractions and mixed numbers with like denominators, using visual models and equations to represent the problem

4.NF.B.3

4.NF.B.3: Understand a fraction a/b with a > 1 as a sum of fractions 1/b. a. Understand addition and subtraction of fractions as joining and separating parts referring to the same whole. b. Decompose a fraction into a sum of fractions with the same denominator in more than one way, recording each decomposition by an equation. Justify decompositions, e.g., by using a visual fraction model. Examples: 3/8 = 1/8 + 1/8 + 1/8; 3/8 = 1/8 + 2/8; 2 1/8 = 1 + 1 + 1/8 = 8/8 + 8/8 + 1/8. c. Add and subtract mixed numbers with like denominators, e.g., by replacing each mixed number with an equivalent fraction, and/or by using properties of operations and the relationship between addition and subtraction. d. Solve word problems involving addition and subtraction of fractions referring to the same whole and having like denominators, e.g., by using visual fraction models and equations to represent the problem.