Skip Counting by 10s - First Grade Mathematics

Of all the skip counting patterns in the universe, skip counting by 10s is the champion of speed! Because our entire number system is built in base-ten, counting by tens is smooth, simple, and powerful. Every time you count by tens, you are counting whole bundles of ten at once without having to count single units. You use skip counting by 10s when counting dimes, organizing large collections of items, and reading the decade markers on charts. In this chapter, you will master skip counting by 10s up to 100 and 120, and explore how place value makes this pattern work.

The Skip Counting Sequence by 10s

Counting by 10s means jumping forward ten whole spaces on every hop.

Hopping by 10s to 100:
10 -> 20 -> 30 -> 40 -> 50 -> 60 -> 70 -> 80 -> 90 -> 100

The Zero at the End

Look at every number in the sequence: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100. Every single number ends with a 0 in the ones place! This zero tells us that there are zero extra single units; each number is made of pure, complete groups of ten.

The Growing Tens Digit

Look at the tens digit (the digit on the left): In 10, there is 1 ten. In 20, there are 2 tens. In 30, there are 3 tens. In 40, there are 4 tens. The tens digit simply counts: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10!

Modeling Tens with Base-Ten Rods

Visualizing rods of ten makes skip counting concrete.

Counting Rods of Ten:
Rod 1: [==========] -> 10
Rod 2: [==========] -> 20
Rod 3: [==========] -> 30
Rod 4: [==========] -> 40
Rod 5: [==========] -> 50
Rod 6: [==========] -> 60
Rod 7: [==========] -> 70

Each Rod Equals 10 Cubes

You do not have to count the ten little notches on each rod. Once you know a rod has a value of ten, you simply touch each rod and say: "10, 20, 30, 40, 50, 60, 70!"

Counting Dimes

The dime is a small silver coin worth exactly 10 cents.

Counting 5 Dimes:
 (10c)      (10c)      (10c)      (10c)      (10c)
   |          |          |          |          |
  10c        20c        30c        40c        50c
Total: 5 dimes = 50 cents!

Dimes to Dollars

Ten dimes make 100 cents, which equals one whole dollar! Skip counting by 10s lets you count money quickly and accurately.

Practice Exercises

Exercise 1: Recite and write down the sequence of skip counting by 10s from 10 up to 100.

Exercise 2: Fill in the missing numbers: 20, 30, , 50, 60, , 80, __, 100.

Exercise 3: You have 7 dimes in your coin pouch. Each dime is worth 10 cents. How many cents do you have in total?

Exercise 4: What number comes after 100 when you are skip counting by 10s, and what number comes after that?

Solutions and Explanations

Solution to Exercise 1: The sequence counting by 10s from 10 to 100 is: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100.

Solution to Exercise 2: The missing numbers are 40, 70, and 90. The complete sequence is 20, 30, 40, 50, 60, 70, 80, 90, 100.

Solution to Exercise 3: Counting 7 dimes by 10s: 10, 20, 30, 40, 50, 60, 70. You have 70 cents in total.

Solution to Exercise 4: When skip counting by 10s, the number that comes after 100 is 110 (one hundred ten), and the number that comes after that is 120 (one hundred twenty).