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:

• Roll & Build
• The Very Hungry Caterpillar

1.NBT.B.2.a. 10 can be thought of as a bundle of ten ones–-called a “ten.”

• No tasks yet illustrate this 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.

• No tasks yet illustrate this 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).

• No tasks yet illustrate this standard.