Multiply one-digit whole numbers by multiples of 10 in the range 10–90 (e.g., 9 × 80, 5 × 60) using strategies based on place value and properties of operations.
Measurement Topic
This standard is reported on the report card in these quarters as follows:
3rd Grade Students Learning 3rd Grade Standards
Quarter 1
Quarter 2
Quarter 3
Quarter 4
Report Card Measurement Topic: Demonstrates understanding of multiplication.
Learning Targets
Multiply one-digit numbers by 10.
Explain how multiplication with multiples of 10 is related to basic facts. (e.g. 4 x 5 = 20, 4 x 5 tens = 20 tens, so 4 x 50 = 200).
Use place value and properties to multiply multiples of 10 (e.g., 9 x 80 = 9 x (8 x 10) = (9 x 8) x 10; or 9 x 80 = (9 x 50) + (9 x 30).
About the Math
Multiply one-digit numbers by 10.
Multiplying numbers by 10 is a foundational understanding for multiplying by multiples of ten. First, students should understand that 4 x 10 is the same as 4 tens or 40. This should be transferred to other digits times 10. This understanding is critical as multiplying by 10 is more than simply adding a zero.
Explain how multiplication with multiples of 10 is related to basic facts. (e.g. 4 x 5 = 20, 4 x 5 tens = 20 tens, so 4 x 50 = 200).
Use place value and properties to multiply multiples of 10 (e.g., 9 x 80 = 9 x (8 x 10) = (9 x 8) x 10; or 9 x 80 = (9 x 50) + (9 x 30).
Students must show evidence of understanding with the first learning target before working with this learning target. Here, students look for patterns between basic facts and related multiplication situations. Students should understand that 5 x 3 is 15 and so 5 x 30 or 3 tens is 15 tens which are 150. Avoid introducing the traditional multi-digit algorithm for this standard. Instead, emphasize multiplying the factors and adding a zero. Talk about why the 0 is there. Multiply 3 x 10, 20, 30, 40, etc and 3 x 1, 2, 3, 4. Discuss the patterns and similarities. Have students build models of 3 x 10, 20, 30, etc to develop an understanding of what is happening mathematically. Encourage students to multiply these numbers mentally as often as possible and use a tool such as a calculator or multiplication chart to check for accuracy.
Progression of Standard within Grade 3
This progression informs how to develop the standard within the grade level. This progression is provided by HCPSS Elementary Mathematics.
Progression Throughout Year
Quarter 1
Quarter 2
Quarter 3
Quarter 4
Model multiplication with multiples of 10 using base ten models and drawings.
Explain how multiplication with multiples of 10 are related to basic facts. (e.g. 4 x 5 = 20, 4 x 5 tens = 20 tens, so 4 x 50 = 200).
Use place value and properties to multiply multiples of 10 (e.g., 9 x 80 = 9 x (8 x 10) = (9 x 8) x 10; or 9 x 80 = (9 x 50) + (9 x 30).
These tasks can be used with small group or whole group instruction.
Give each student some ones and tens from the base ten blocks in your room. Review what the units (ones) and rods (tens) represent. Ask students to represent 3 groups of 1 with the blocks. Ask students to write what multiplication equation matches the prompt (3x1=3). Ask students to then represent 3 groups of 10 with the blocks and write the multiplication equation that matches (3x10=30). Repeat with 7 groups of 1 and 7 groups of 10 with corresponding equations. Teacher should collect the examples on chart paper and ask what patterns the students are noticing.
Continuing from the first bullet above... Students using the base ten blocks, the teacher poses a scenario: At ABC Elementary, there are four 2nd grade classroom and each class has 20 students. Ask students to build a representation to match the scenario (4 groups with 2 base ten rods in each group) and ask students to write the matching equation (4x20=80). Repeat using other scenarios (5 jars with 30 pencils in each, 2 packs of crayons with 50 crayons in each, 3 boxes with 40 markers in each, 2 buses with 60 students on each) and the teacher should collect the equations on chart paper. Ask students to look the equations they have created and ask them to describe any patterns they notice. It is likely they will see that they are "multiplying the numbers and adding a zero". This is a great observation and the teacher's role is to connect that observation to the associative property that has already been learned... 4x20 is the same as 4x2x10 and 5x30 is the same as 5x3x10. This explains why the math (and the observed pattern) works.
Lukas says that he can’t finish his homework because he doesn’t know how to multiply 5 x 70. Explain a strategy to help him solve this problem.
How would adding a 0 to the end of a number affect the value of the digits? (e.g., 75 becoming 750)
Describe the pattern you see when you multiply 3 x 4 and then 3 x 40.
How are the products of 5 x 5 and 5 x 50 similar? How are they different?
How does multiplying 10 x 8 help you to solve 9 x 8?
Explain how multiplying by multiples of 10 is similar to multiplying by one-digit numbers.
4 x 4 = 16 and 4 x 40 = 160. 4 x 5 = 20 and 4 x 50 = 200 Use the pattern you see to solve 4 x 60 and 4 x 70.
Explain why these expressions are equal: 6 x 30 = (6 x 3) x 10 Give another example using the Distributive Property
Explain why these expressions are equal: 40 x 7 = (20 x 7) + (20 x 7) Give another example by breaking apart one of the factors.
Use what you know about multiples of 10 to explain why the product of 8 x 5 is 16 more than the product of 8 x 3.
Slide-Based Tasks
These links are HCPSS created instructional tasks. These tasks are provided in Google slides. These tasks should be used for inspiration and resources, but instruction should start with students having the opportunity to engage with the math first (often involving physical and/or visual models) followed by discussion and explicit instruction to ensure student understanding.
These publications have been provided for each school. They are typically stored in team closets or the media center. Check with your team leader if you cannot find them.
These resource sheets can be used for independent practice or homework. They are intended to reinforce procedures and concepts. They should not be used as a source of direct instruction or whole-group practice.
Explain how multiplication with multiples of 10 are related to basic facts. (e.g. 4 x 5 = 20, 4 x 5 tens = 20 tens, so 4 x 50 = 200).
Use place value and properties to multiply multiples of 10 (e.g., 9 x 80 = 9 x (8 x 10) = (9 x 8) x 10; or 9 x 80 = (9 x 50) + (9 x 30).
Learning targets identify what students should be able to do. The resources below can be used to measure student understanding of the standard. This rubric can be applied to tasks and observations for assessment and/or grading.