Kentucky Academic Standards
Numbers and Operations in Base Ten
Cluster: Understand place value.
KY.1.NBT.2. Understand the two-digits of a two-digit number represent amounts of tens and ones. Understand the following as special cases: (MP.5, MP.7)
KY.1.NBT.2.a. 10 can be thought of as a bundle of ten ones—called a “ten.”
KY.1.NBT.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.
KY.1.NBT.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).