CCSS.Math.Content.1.NBT.B.2b
The standard
The numbers from 11 to 19 are composed of a ten and one, two, three, four, five, six, seven, eight, or nine ones.
Common Core State Standards for Mathematics
What this standard means
Students need to see teen numbers as one group of ten plus some extra ones. They should build, draw, say, and write numbers 11 through 19 using tens and ones language, like 14 is 1 ten and 4 ones.
Mastery looks like a student making 17 with a ten-stick and 7 cubes, then explaining it without counting all from 1. Common trouble spots are saying 13 as 3 tens, reversing digits, or treating teen numbers as memorized names instead of ten plus ones.
Ways to teach it
- Have students build each teen number with a ten-frame or bundle of 10 straws and loose ones, then label it with a numeral card.
- Ask, “How is 16 different from 6?” and have students answer with a drawing, cubes, or a sentence frame.
- Show 1 ten-stick and 8 cubes, then ask students to write the number and say how many tens and ones.
- Use a carton of 10 eggs plus loose plastic eggs to show teen amounts as one full ten and extra ones.
Plan a lesson for CCSS.Math.Content.1.NBT.B.2b
Generate a complete lesson plan aligned to this standard, with objectives, activities, and materials. Free, no account needed.
Related standards
- CCSS.Math.Content.K.NBT.A.1
Compose and decompose numbers from 11 to 19 into ten ones and some further ones, e.g., by using objects or drawings, and record each composition or decompositio...
- CCSS.Math.Content.1.NBT.B.2a
10 can be thought of as a bundle of ten ones — called a "ten."
- CCSS.Math.Content.2.NBT.A.1b
The numbers 100, 200, 300, 400, 500, 600, 700, 800, 900 refer to one, two, three, four, five, six, seven, eight, or nine hundreds (and 0 tens and 0 ones).
- CCSS.Math.Content.1.NBT.B.2c
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).