Standard: 1.NBT.B2c – The numbers 10, 20, 30, 40, 50, 60, 70, 80, 90 refer to one, two, three, four, five, six, seven, eight, or nine tens (and 0 ones).
Grade level: Grade 1
Subject: Mathematics
Domain: Number & Operations in Base Ten
Teacher Overview
This standard focuses on understanding that numbers like 10, 20, 30, etc., are composed of whole tens and zero ones. This concept is crucial as it lays the foundation for place value, which is essential for arithmetic operations and understanding larger numbers. Students should be comfortable with counting up to 100, recognizing numbers, and understanding basic counting principles such as ‘one more’ and ‘one less.’
After mastering this standard, students will be able to perform addition and subtraction within 100, understand place value for three-digit numbers, and solve word problems involving tens and ones.
Common Misconception 1
Some students may think that the numbers 10, 20, 30, etc., are just arbitrary numbers without realizing they represent groups of ten. This misunderstanding can hinder their grasp of place value.
Intervention 1
Use visual aids like ten-frames or bundles of sticks to show how these numbers are composed of tens. Reinforce this with hands-on activities.
Common Misconception 2
Another common misconception is that numbers like 10, 20, 30, etc., include ones in addition to tens. This can confuse students when they start performing arithmetic operations.
Intervention 2
Provide exercises where students break down numbers into tens and ones, emphasizing that these specific numbers have zero ones. Use manipulatives to make this concept more tangible.
Prerequisite Knowledge
Students should be able to count to 100, understand the concept of ‘one more’ and ‘one less,’ and recognize and write numbers from 1 to 10.
Subsequent Knowledge
Students will develop the ability to perform addition and subtraction within 100, understand place value for three-digit numbers, and solve word problems involving tens and ones.
Instructional Activities
- Counting dimes and pennies
- Grouping objects into sets of ten
- Using bundles of ten sticks in classroom activities
- Reading and writing numbers in tens
- Using ten-frames to visualize numbers
