Foundations Sampler 2024

B2 Lesson Plans 66 ©MathTeachersPress, Inc.Reproduction by anymeans is strictly prohibited. 66 1. ____ ____= _____ ____ ____= _____ ____ ÷ ____= _____ ____ ÷ ____= _____ 2. ____ ____= _____ ____ ____= _____ ____ ÷ ____= _____ ____ ÷ ____= _____ Relating Multiplication and Division in Fact Families Multiplication and division are opposite operations because one undoes the other. A set of related multiplication and division number sentences is called a fact family . Use 6, 7 and 42 towrite 2 division and 2multiplication facts for the picture. 42 ÷ _____= ____ ____ = ____ ____ = Write 2 multiplication facts and 2 division facts for each array. Write the other three sentences in the fact family. Write the missing number for each triangle fact card. 3. 7 8 = 56 ___________________ ___________________ ___________________ 4. 6 7 = 42 ___________________ ___________________ ___________________ 5. 7 9 = 63 ___________________ ___________________ ___________________ 6. 7. 8. Which number sentence is not in the same fact family as the other 3 number sentences? A 3 8 = 24 B 24 ÷ 3 = 8 C 24 ÷ 8 = 3 D 24 = 6 4 A B C D 56 ÷ ÷ 7 63 ÷ ÷ 7 ÷ ÷ 7 6 There are 7 columns of6. The inverse division fact is… The inverse division fact is… There are 6 rows of 7. 42 ÷ _____= Division Multiplication 6 7 42 7 6 7 6 42 6 7 7 5 35 7 2 14 5 7 35 2 7 14 35 5 7 14 2 7 35 7 5 14 7 2 7 x 8 = 56 7 x 6 = 42 9 x 7 = 63 56 ÷ 7 = 8 42 ÷ 7 = 6 63 ÷ 7 = 9 56 ÷ 8 = 7 42 ÷ 6 = 7 63 ÷ 9 = 7 42 8 9 Objective: To relate multiplication and division as opposites. To write related facts in a fact family. Materials: Interlocking cubes and One-Inch Graph Paper (Master 5), half sheets of paper Vocabulary: fact family, opposite operations A Classroom Model Each group will need cubes and a sheet of One-Inch Graph Paper. Ask students to arrange the desks in the classroom in rows with each row having the same number of desks. (Leftover desks aren’t used for the example.) Today the desks have been arranged in rows. Each row has the same number of desks. What mathematical model have we made with our desks? (an array) How many rows? How many desks in each row? Use your cubes to make a model of the classroom. Then write a number sentence to find how many desks in all. For example, if there were 5 rows with 6 desks in a row, students could write 5 6 = 30 or 6 5 = 30. What if we know the total number of desks and the number of rows, but want to find how many desks are in each row? (30 ÷ 5 = 6) Write a number sentence to find the number of rows if we know the total number of desks and the number of desks in each row. (30 ÷ 6 = 5) These 4 number sentences are a fact family relating 5, 6 and 30 with the operations of multiplication and division. Multiplication puts groups of the same number together. Division takes groups of the same number apart. Multiplication and division are opposite operations, one operation undoes the other. Write on the board: The band room has 35 chairs arranged in 5 rows. Each row has the same number of chairs. Draw a picture of the band room and write the 4 related facts in the fact family. Read the information and find the missing numbers in the example at the top of the page. Work problems 1, 3, and 6 together. Students complete the page on their own. Students who did not choose C do not understand that fact families use the same 3 numbers. ERRORANALYSIS TestPrep 5 7 5 7 = 35 7 5 = 35 35 ÷ 7 = 5 35 ÷ 5 = 7 Writing Fact Families Each student will need several half sheets of paper. Show students how to fold the paper in half two times to make 4 parts. Write the following trios of numbers on the board: 6, 7, 42 6, 8, 48 6, 9, 54 7, 8, 56 Have students write four related facts in each of the 4 parts. Example: Some trios do not have 4 different, yet related facts. Can you think of 2 numbers that do not? (any square number, e.g., 5 5, 6 6, 7 7, etc.) Write the related facts for 6 6 and 7 7. a. 6 7 = 42 b. 7 6 = 42 c. 42 ÷ 7 = 6 d. 42 ÷ 6 = 7 Relating Multiplication and Division Relating multiplication and division with fact families Sample of Scripting (Bold Type) row, students could write 5 6 = 30 or 6 5 = 30. What if we know the total number of desks and the number of rows, but want to find how many desks are in each row? (30 ÷ 5 = 6) Wr e a number sentence to find the number of rows if we kn w the total number of desks and the number of desks in each row. (30 ÷ 6 = 5) These 4 number sentences are a fact family relating 5, 6 and 30 with the operations of multiplication and division. Multiplication puts groups of the same number tog ther. Division takes groups of the same number apart. Mul iplication and division are opposite operations, one operation undoes the other. B2 Lesson Plan 33