Unit 2

Multi-Digit Whole Number and Decimal Fraction Operations and Measurement Conversions

 

Grade 5

Math

Description:

 

Students will use place value understanding and properties of operations to perform multi-digit operations with whole numbers and decimals.  Students multiply multi-digit numbers. Students understand the distributive property.  Students divide by two-digit divisors.  Students will use strategies, illustrations, and explanations including models to divide.

 

Students apply their knowledge of place value, decimals, multiplication and division to conversions within the metric system and to solve multi-step problems through modeling and writing simple equations. 

 

Louisiana Student Standards for Mathematics (LSSM)

NBT - Number and Operation in Base Ten

Understand the place value system.

5.NBT.A.1

Recognize that in a multi-digit number, a digit in one place represents 10 times as much as it represents in the place to its right and 1/10 of what it represents in the place to its left.

5.NBT.A.2

Explain patterns in the number of zeros of the product when multiplying a number by powers of 10, and explain patterns in the placement of the decimal point when a decimal is multiplied or divided by a power of 10.  Use whole-number exponents to denote power of 10.

5.NBT.A.4

Use place value understanding to round decimals to any place.

5.NBT.B.5

Fluently multiply multi-digit whole numbers using the standard algorithm.

5.NBT.B.6

Find whole-number quotients of whole numbers with up to four-digit dividends and two-digit divisors, using strategies based on place value, the properties of operations, subtracting multiples of the divisor, and/or the relationship between multiplication and division.  Illustrate and/or explain the calculation by using equations, rectangular arrays, area models or other strategies based on place value.

5.NBT.B7

 

Add, subtract, multiply, and divide decimals to hundredths, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; justify the reasoning used with a written explanation.

MD – Measurement and Data

Convert like measurement units within a given measurement system.

5.MD.A.1

 

Convert among different-sized standard measurement units within a given measurement system and use these conversions in solving multi-step, real world problems. (e.g., convert 5 cm to 0.05 m; 9 ft to 108 in).

OA – Operations and Algebraic Thinking

Write and interpret numerical expressions

5.OA.A.1

Use parentheses or brackets in numerical expressions, and evaluate expressions with these symbols.

 

5.OA.A.2

 

 

Write simple expressions that record calculations with whole numbers, fractions, and decimals, and interpret numerical expressions without evaluating them. For example, express the calculation “add 8 and 7, then multiply by 2” as 2 × (8 + 7). Recognize that 3 × (18,932 + 9.21) is three times as large as 18,932 + 9.21, without having to calculate the indicated sum or product.

 

Enduring Understandings:

 

·         The properties of multiplication and division help us solve computation problems.

·         There is an order of operations that must be followed in all mathematical expressions.

·         Selection of measurement tools and units depends on the real-world situation.

·         Decimals allow us to express quantities with greater precision.

 

Essential Questions:

 

·         How can I write an expression that demonstrates a situation or context?

·         Why express measurements in different ways?

·         How does the position of a digit affect its value?

·         Why is it important to follow an order of operations?

·         How does multiplying or dividing a number by a power of ten affect the product or quotient?