Standard: 3.NBT.A3 – 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.
Grade level: Grade 3
Subject: Mathematics
Domain: Number & Operations in Base Ten
Teacher Overview
This standard focuses on multiplying one-digit whole numbers by multiples of 10, an essential skill in developing students’ understanding of place value and the properties of operations. Mastery of this standard lays the groundwork for more complex multiplication and division tasks. Ensure students have a solid understanding of basic multiplication facts and place value concepts, particularly recognizing the value of digits in different places.
After mastering this standard, students will be prepared to tackle more complex multiplication problems involving multi-digit numbers and develop strategies for solving larger multiplication tasks efficiently.
Common Misconception 1
A common misconception is that multiplying by 10 simply means adding a zero to the end of the number. This is incorrect because it overlooks the place value concept where each digit shifts one place to the left.
Intervention 1
Use place value charts and manipulatives to demonstrate how each digit moves one place to the left when multiplying by 10. Reinforce this with various examples and practice problems.
Common Misconception 2
Another misconception is confusing multiplication with addition, such as thinking 5 × 60 is the same as 5 + 60. This error arises from a lack of understanding of multiplication as repeated addition.
Intervention 2
Use visual aids like arrays and grouping to illustrate multiplication as repeated addition. Provide multiple practice opportunities with different numbers to solidify this understanding.
Prerequisite Knowledge
Students should understand basic multiplication facts and have a solid grasp of place value concepts, particularly the value of digits in the tens place.
Subsequent Knowledge
Students will develop the ability to multiply multi-digit numbers and understand more complex multiplication strategies, leading to proficiency in solving larger multiplication problems.
Instructional Activities
- Use place value charts to demonstrate multiplication by 10.
- Practice problems multiplying one-digit numbers by multiples of 10.
- Group activities where students create arrays for multiples of 10.
- Real-world examples such as calculating total items in packs of 10.
