Computer Science Lesson Plan
Class: 7 - Lesson: 3 Variables and Operators

Purpose: To learn to use the controls available in Scratch - motion, looks, events, variables and operators.

No. of Classes

One or two classes (teacher's decision).

Material Required

Scratch 3.0.

Curriculum Content
  • 2.4) Conditional Statement
  • 2.6) Variables
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  • 4.3) Operators (6th Std)
  • 5.3) Costumes (6th Std)
  • 5.4) Motion (6th Std)
  • 5.5) Looks (6th Std)
    •

    Prior Knowledge

    Students should know:

  • Sprites, backdrops, costumes and sound.
  • Computational thinking skills developed through problem-solving games.

    • Exercises

    Exercise 1


    1. Create a variable and name it "bananas". When the monkey touches the banana, increase the variable by 1. Change the backdrop when the variable exceeds 10 and again when it exceeds 15, and finish the game when it exceeds 20. Students can create their own games, such as apple catching or a dog chasing a ball.

    Exercise 2


    1. Create a program that carries out the basic operations (add, subtract, multiply, divide) using two values entered by the user.

    Exercise 3


    1. Create a program in which the sprite asks the user some questions. The sprite then stores all the answers using variables and displays them.

    Solutions


  • Link to copy the solution program for Exercise 1.
  • Link to view the solution video for Exercise 1.
  • Link to copy the solution program for Exercise 2.
  • Link to view the solution video for Exercise 2.
  • Link to copy the solution program for Exercise 3.
  • Link to view the solution video for Exercise 3.

    • Teacher Instructions
    1. Teachers should recall the concept of programming.
    2. Teachers should teach all the operators in the Operators blocks.
    3. Teachers should teach how to create variables, with examples.
    4. Teachers should teach how to initialise the value of a variable.
    5. Click here for more reference material for this lesson.