2.

Multiples of 10 - 1st Grade Math

Multiples of 10 Worksheet focuses on helping the students understand that the numbers 10, 20, 30 etc refer to one, two, three tens. A group of 10 ones can be thought of as 1 ten; 2 such groups make 2 tens and so forth. 

Common Core Alignment

1.NBT.2.cThe 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).

1.NBT.2Understand that the two digits of a two-digit number represent amounts of tens and ones. Understand the following as special cases: