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Session 31: The Multiples Mysteries

Session Title

The Multiple Mysteries 

Objective

By the end of this session, students will be able to:


1.

  1. Understand the concept of the Least Common Multiple (LCM)

2.

Find the LCM of the given numbers using different methods.

3.

Develop problem-solving and teamwork skills

 

Concepts

    The Least Common Multiple (LCM) is the smallest multiple that two or more numbers share.

    It is useful in real-life applications, such as scheduling events, solving fraction problems, and understanding patterns.

    Materials Required
    1. Board & Chalk 
    2. Before starting the class, draw a number grid ( up to 50 ) on the floor

    Methodology
    1. Activity-based Learning: Physical activity and group work.
    2. Experiential Learning: Relating LCM to real-life situations.

    Session Duration

    		 12090 Minutes

    Introduction Activity 

    GAME TIME

    Pass pass - (10 Minutes)


    Game Time : Pass pass 

    In "Pass Pass," children form a circle. A target numbernumber( Eg: multiple of 2 or 3) is chosen. Starting with the first child, they count aloud in sequence. When a child's count reaches a multiple of the target number, they say "Pass" instead of the number.number(Eg : target number is 5. 1,2,3,4,pass,6,7.....) The next child continues the count. The game continues until only one child remains.(NB: Change the number after each round)


    Main Topic/ Activity


    Objective: Help students relate LCM to everyday life.


    Tell a short story:- ( 20 minutes )


    Two friends, Arya and Rahul, love visiting a park. Arya visits every 3 days, and Rahul visits every 4 days. If both visit the park today, when will they meet again?


    Ask students to think and predict: “Will they meet again in a week? In 10 days?”


    Guide them to count the days until both are at the park together (on the 12th day).


    Explain

    Explnumbersnumbers at the Least Common Multiple (LCM) of 3 and 4 is 12—the smallest number that both 3 and 4 can divide into evenly.



    DEMO TIME  ( 30 minutes )


    1. Draw a number grid on the floor (1–50)


    2. Call out two numbers (e.g., 4 and 6)


    3. Students take turns hopping on the multiples (4, 8, 12… and 6, 12, 18…)


    4. The first common number they step on is the LCM 

     ( NB: Repeat the activity with different number )


    TIME TO SOLVE: ( 20 Minutes)


    Give simple examples: ( Devide students into small groups)


    • LCM of 2 and 5 

    → Multiples: (2, 4, 6, 8, 10, 12…) and (5, 10, 15…) → LCM is 10.


    • LCM of 6 and 8

    → Multiples: (6, 12, 18, 24…) and (8, 16, 24…) → LCM is 24.


    • A bell rings every 6 minutes, and another bell rings every 8 minutes. After how many minutes will both bells ring together?


    • A school organizes a sports day every 5 years, and a cultural fest every 7 years. How many years later will both events happen together again?


    Expected Learning  Outcome:


    Knowledge building-

    • Concept of LCM

    • Method to find LCM


    Skill Building-

    • Logical thinking

    • Strengthens speed and accuracy

    • Team work 


    Review Questions/Assessment/Tasks 


    Ask: What strategies helped you solve the problems quickly?


    Encourage peer teaching—students explain their solutions to classmates.


    Follow up Task


    Home work: ( 10 minutes)

    1.Two farmers plant crops—one plants every 9 days, and the other every 12 days. In how many days will they plant on the same day again?


    2.Two buses leave a station at the same time—one after 12 minutes, the other after 15 minutes. When will they leave together again?

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