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Learning Resource Type

Learning Activity

Decomposing Numbers: Part 3

Subject Area





In this activity, students will demonstrate and apply their knowledge of decomposing a number in a variety of ways and recording their decomposition using pictures, numbers, or equations.

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 demonstrate and apply their understanding of decomposing a number in a variety of ways and recording their decomposition using pictures, numbers, or equations.

    Activity Details

    1. The teacher will give each student a copy of the Five Fish fish and fishbowl activity page (teacher can chose to provide colored page or black and white and have students color the fish).

    2. The teacher will instruct students to cut out all fish. These will be used as manipulatives to complete the activity.

    3. The teacher will give each student a Five Fish Recording sheet (four different options have been provided, the teacher can choose what best meets the needs of their students).

    4. The teacher will read the question to the students, "There are 5 fish in the bowl. Some are orange, some are purple. How many fish are orange? How many fish are purple?"

    5. If needed, the teacher will demonstrate using a combination of orange and purple fish to create a total of 5.

    6. Students will work to create as many combinations of 5 as they can using the fish as manipulatives and recording their answers on the recording sheet.

    Assessment Strategies

    Assessment Strategies

    Assessment of Recording Sheet: The teacher will note whether students were able to decompose 5 in multiple ways.

    Variation Tips

    This activity can be done with any number 2-10 depending on student needs.

    Students can use a number balance or an online number balance to demonstrate/check the equality of each pair of numbers to 5 (ex: 5 on one side of the number balance, 4 and 1 on the other side to demonstrate the equality of the two sets of numbers).

    Background and Preparation

    Background / Preparation

    The teacher will need to prepare:

    1 pair of scissors per student.

    Five Fish activity sheet for each student.

    Five Fish recording sheet for each student.

    Digital Tools / Resources