Domain 1.NBT, Number and Operations in Base Ten

Cluster 1.NBT.A, Extend the counting sequence.

Major Cluster

Standard 1.NBT.A.1

Count to 120, starting at any number less than 120. In this range, read and write numerals and represent a number of objects with a written numeral.

9 Lessons

34 Activities

Cluster 1.NBT.B, Understand place value.

Major Cluster

Standard 1.NBT.B.2

Understand that the two digits of a two-digit number represent amounts of tens and ones. Understand the following as special cases:

19 Lessons

38 Activities

Standard 1.NBT.B.2.A

10 can be thought of as a bundle of ten ones - called a "ten."

7 Lessons

6 Activities

Standard 1.NBT.B.2.B

The numbers from 11 to 19 are composed of a ten and one, two, three, four, five, six, seven, eight, or nine ones.

2 Lessons

10 Activities

Standard 1.NBT.B.2.C

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).

4 Lessons

2 Activities

Standard 1.NBT.B.3

Compare two two-digit numbers based on meanings of the tens and ones digits, recording the results of comparisons with the symbols >, =, and <

14 Lessons

21 Activities

Cluster 1.NBT.C, Use place value understanding and properties of operations to add and subtract.

Major Cluster

Standard 1.NBT.C.4

Add within 100, including adding a two-digit number and a one-digit number, and adding a two-digit number and a multiple of 10, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used. Understand that in adding two-digit numbers, one adds tens and tens, ones and ones; and sometimes it is necessary to compose a ten.

35 Lessons

53 Activities

Standard 1.NBT.C.5

Given a two-digit number, mentally find 10 more or 10 less than the number, without having to count; explain the reasoning used.

11 Lessons

39 Activities

Standard 1.NBT.C.6

Subtract multiples of 10 in the range 10-90 from multiples of 10 in the range 10-90 (positive or zero differences), using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used.

1 Lesson

7 Activities