CCSS.Math.Content.K.NBT.A

CCSS.Math.Content.K.NBT.A is a cluster heading. These are the individual standards under it.

• 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...

01

What Students Need to Do

Students make numbers 11 through 19 using one group of ten and 1 to 9 extra ones. They match objects, drawings, spoken number names, and numerals.

02

What Mastery Looks Like

Students build, draw, and explain any number from 11 through 19 as one ten and some ones. They connect the model to the written numeral, such as 16 meaning 10 and 6 more.

03

Common Misconceptions

Students may read 14 as 41 or think the first digit tells how many ones there are. They may count 13 objects correctly but not see a group of ten and 3 extras. Some think the word “teen” means the same extra amount in every teen number.

04

How to Assess It

Give each student the number 17 and 20 counters. Ask them to show 17 as one group of ten and some extra ones, then label both parts.

1. 01

   Give students linking cubes to build each teen number as one stick of ten and a separate group of extra cubes.

2. 02

   Show 15 as ten dots and five dots, then ask, “How does each part match a digit in 15?”

3. 03

   Play Teen Number Match with cards showing numerals, ten-frames, cube trains, and equations such as 10 + 8.

4. 04

   Count classroom items into a full bag of ten and leftovers, then label the total with a teen numeral.

• CCSS.Math.Content.1.NBT.B

  Understand place value.

• CCSS.Math.Content.2.NBT.B.6

  Add up to four two-digit numbers using strategies based on place value and properties of operations.

• CCSS.Math.Content.2.NBT.A

  Understand place value.

• CCSS.Math.Content.5.NBT.A

  Understand the place value system.