Before You Begin This Unit... |
Unit at a Glance |
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In early grades, students have worked on skip counting by smaller numbers and solved problems by making equal groups. In 3^{rd} grade, students develop an understanding the concept of multiplication as an action used to combine a number of equal-sized groups. Division is also introduced in 3^{rd} grade as an operation used to solve problems when an amount is divided into groups and either the number of equal-sized groups or the size of the groups must be determined. The focus of this unit is two-fold. Students will work on developing strategies for multiplication and division of larger numbers in this unit. Keeping track of all the parts of a problem that involves multi-digit numbers will be a part of class discussions as you support your students in this work. Students also focus on representing multiplication and division situations and understanding the relationship between these operations. As students create representations (such as arrays), encourage them to explain how they break apart problems and keep track of the problem parts. |
Suggested Dates: September 22- October 17 Estimated Duration: 20 days Investigation 1 - 4 days Omit the question 14 x 12 in lesson 1 and workbook page 1. In this unit we are only multiplying 2 by 1 digit. Combine 1.3-1.5 in 2 days. Investigation 2 – 6 days Investigation 3 – 4 days Lesson 3.3 Instead of 15 x 13, do a multiplication problem using multiple of 10 for example 50 x 3 or 5 x 30. Investigation 4 – 5 days |
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Standards Addressed in the Unit | |||
Link to the CCSS Unpacking Document- Updated Sept. '15
4.OA.2 Multiply or divide to solve word problems involving multiplicative comparison, e.g., by using drawings and equations with a symbol for the unknown number to represent the problem, distinguishing multiplicative comparison from additive comparison.
4.OA.3 Solve multistep word problems posed with whole numbers and having whole-number answers using the four operations, including problems in which remainders must be interpreted. Represent these problems using equations with a letter standing for the unknown quantity. Assess the reasonableness of answers using mental computation and estimation strategies including rounding.
4.OA.4 Find all factor pairs for a whole number in the range 1–100. Recognize that a whole number is a multiple of each of its factors. Determine whether a given whole number in the range 1–100 is a multiple of a given one-digit number. Determine whether a given whole number in the range 1–100 is prime or composite.
4.NBT.5 Multiply a whole number of up to four digits by a one-digit whole number, and multiply two two-digit numbers, using strategies based on place value and the properties of operations. Illustrate and explain the calculation by using equations, rectangular arrays, and/or area models. 4.NBT.6 Find whole-number quotients and remainders with up to four-digit dividends and one-digit divisors, using strategies based on place value, the properties of operations, and/or the relationship between multiplication and division. Illustrate and explain the calculation by using equations, rectangular arrays, and/or area models |