Parent Support for K-5 Math

Kindergarten Mathematics

Unit 2: Exploring Numbers to 10

What will your child learn in Unit 2?

In Unit 2, kindergartners will count, read, and write numbers to 10. Children will understand that counting tells how many things are in a set. When counting a set of objects, the last word in the counting sequence names the quantity for that set. Counting involves at least two separate skills. First, one must be able to produce the standard list of counting words in order: “One, two, three, four, . . . .” Second, one must be able to connect this sequence in a one-to-one manner with the items in the set being counted. Each item must get one and only one count.

Another goal of Unit 2 is for students to develop a strong number sense, which means a good intuition about numbers and their relationships. Children will experience spatial relationships. They will learn to recognize sets of objects in patterned arrangements and tell how many without counting. To practice this skill, teachers will show students dot images for 3 seconds and ask, “How many did you see? How did you see it?” The picture below is an example of a dot image.

“How many did you see? How did you see it?”
“How many did you see? How did you see it?”

The ability to tell how many without counting is called subitizing. Check out the videos below for more examples.

Additionally, students will work on one and two more, one and two less number relationships to build strong number sense. The two-more-than and two-less-than relationships involve more than just the ability to count on two or count back two. Children should know that 7, for example, is 1 more than 6 and also 2 less than 9. They will also learn benchmarks of 5 and 10. Since 10 plays such a large role in our number system and because two fives make up 10, it is very useful to develop relationships for the numbers 1 to 10 to the important anchors of 5 and 10. Furthermore, students will work on part-part-whole relationships. To conceptualize a number as being made up of two or more parts is the most important relationship that can be developed about numbers. For example, 7 can be thought of as a set of 3 and a set of 4 or a set of 2 and a set of 5. They will practice decomposing and composing numbers to work on this skill.


What number relationships will your child explore in Unit 2?

Explanation of Number Relationships

Check out the video below to see how dot images can be used to strengthen spatial arrangements.

How can you support your child at home to reinforce the concepts taught in Unit 2?

There are several ways to have your child practice the math concepts at home. Try the following activities:

  • Have your child practice counting a variety of objects. Make sure each object gets one and only one count.
  • Visit Okta’s Rescue to have your child practice counting and subitizing.
  • Visit Concentration to have your child find different representations of numbers. Click Levels 1-6 or 1-10.
  • Visit Five Frame to have your child develop counting and addition skills.
  • Visit Ten Frame to have your child develop counting and addition skills.
  • Visit the online rekenrek (number rack) to help your child make numbers a different ways. Click the “i” on the bottom of the website for instructions on how to use it.
  • Visit Number Pieces to help your child structure numbers to 5 and 10. Children use the frames to count, represent, and compare numbers. Have your child work in the range of numbers 1 to 10. Click the “i” on the bottom of the website for instructions on how to use it.
  • Have your child practice writing and representing numbers by working on Playdough Numbers.
  • Have your child practice forward and backward number sequence by working on Counting Cards.
  • Math Games for Home: Print the handouts to practice concepts through games.