ALEX Classroom Resources

   View Standards     Standard(s): [MA2015] (5) 2 :

2 ) Write simple expressions that record calculations with numbers, and interpret numerical expressions without evaluating them. [5-OA2]

Examples: Express the calculation "add 8 and 7, then multiply by 2" as 2 x (8 + 7). Recognize that 3 x (18,932 + 921) is three times as large as 18,932 + 921, without having to calculate the indicated sum or product.

[MA2019] (5) 1 :

1. Write, explain, and evaluate simple numerical expressions involving the four operations to solve up to two-step problems. Include expressions involving parentheses, brackets, or braces, using commutative, associative, and distributive properties.

[MA2019] (5) 6 :

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

In Module 2, Topic B, place value understanding moves toward understanding the distributive property by using area models to generate and record partial products (5.OA.1, 5.OA.2), which are combined within the standard algorithm (5.NBT.5). Writing and interpreting numerical expressions in Lessons 1 and 2 and comparing those expressions using visual models, lay the necessary foundation for students to make connections between the distributive property, as depicted in area models, and the partial products within the standard multiplication algorithm. The algorithm is built over a period of days, increasing in complexity as the number of digits in both factors increases. Reasoning about zeros in the multiplier, along with considerations about the reasonableness of products, also provides opportunities to deepen understanding of the standard algorithm. Although word problems provide context throughout Topic B, the final lesson offers a concentration of multi-step problems that allows students to apply this new knowledge.

   View Standards     Standard(s): [MA2019] (5) 6 :

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

[MA2019] (5) 8 :

8. Add, subtract, multiply, and divide decimals to hundredths using strategies based on place value, properties of operations, and/or the relationships between addition/subtraction and multiplication/division; relate the strategy to a written method, and explain the reasoning used.

a. Use concrete models and drawings to solve problems with decimals to hundredths.

b. Solve problems in a real-world context with decimals to hundredths.

[MA2019] (5) 17 :

17. Convert among different-sized standard measurement units within a given measurement system and use these conversions in solving multi-step, real-world problems.

In Module 2, Topic D, students explore multiplication as a method for expressing equivalent measures. For example, they multiply to convert between meters and centimeters or ounces and cups with measurements in whole number, fraction, and decimal form (5.MD.1). These conversions offer opportunities for students to not only apply their newfound knowledge of multi-digit multiplication of both whole and decimal numbers but to also reason deeply about the relationships between unit size and quantity (i.e., how the choice of one affects the other). Students are given the opportunity to review the multiplication of a whole number by a fraction, a skill taught in Grade 4.