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Learning Resource Type

Learning Activity

Composing and Decomposing Numbers to 10 Practice

Subject Area





In this activity students will practice decomposing numbers less than or equal to 10 in more than one way while using objects and drawings.

This activity results from the ALEX Resource Development Summit.

    Mathematics (2019) Grade(s): KG


    Decompose numbers less than or equal to 10 into pairs of smaller numbers in more than one way, by using concrete objects or drawings, and record each decomposition by a drawing or equation.

    Unpacked Content



    • Decompose
    • Equation


    Students know:
    • "equal to" and the concept of equality meaning "the same as."
    • Addition is putting together numbers and subtraction is taking apart numbers.


    Students are able to:
    • Represent quantities physically, pictorially, and symbolically.


    Students understand that:
    • quantities may be named in a variety of ways.


    Learning Objectives

    Learning Objectives

    Students will use objects or drawings to decompose a given number into two pairs of smaller numbers and record their solution using pictures or equations.

    Activity Details

    1. Explain to the students that a number bond is used to show how 2 parts can make a whole and a whole can be broken into 2 parts.
    2. Choose any number less than or equal to 10.
    3. Give students a small lunch sack that contains the 10 monkeys and the 10 alligators that were provided to you for printing.
    4. Without looking, have students reach into the bag and pull out 1 object (for this game, picture cards of alligators and monkeys) at a time until they have displayed the given number.
    5. Show the students how they can place all of the monkeys and alligators on the circle labeled whole on the number bond mat. 
    6. Next have them move the monkeys to one of the small circles labeled part and the alligators to the other small circle labeled part on the number bond mat.
    7. Explain that the 2 parts make up the whole.
    8. Encourage the students to verbalize with the group or partner, their decomposition on the number bond mat (I know that 7 is 3 and 4).
    9. Continue to play this game using different numbers less than or equal to 10. 
    10. Once the students have practiced a few times on the number bond mat, have them represent one of their decompositions in their math journal. Students should use drawings and/or numerals for their representation.
    Assessment Strategies

    Assessment Strategies

    1. While students are counting out the monkeys and alligators, the teacher will observe students using one to one correspondence.
    2. While students are working on the number bond mat, the teacher will drop in and listen to see if the student can verbalize the parts and the whole.
    3. Students are able to represent their quantity in their math journal using drawings and/or numerals.

    Variation Tips

    Once the students have mastered verbalizing and representing their decompositions, then move the student towards writing an equation to represent their decomposition (7=3+4 or 3+4=7).

    As you drop and listen, have students cover 1 of the parts or the whole on the number bond mat with a cup and have the partner guess the missing part or whole.

    Background and Preparation

    Background / Preparation

    The teacher will need to print and cut out the alligators and monkeys for each student.

    The teacher will need to print the number bond mat for each student and laminate for this lesson.

    Digital Tools / Resources