🎯 Learning outcomes
- Give precise step-by-step instructions (algorithms) for everyday tasks
- Use sequences, loops and simple conditions in block-based coding
- Find and fix mistakes (debugging)
Before you start: Following instructions.
📖 Explanation
An algorithm is a list of steps to do a task, like a recipe for making lemon water: take a glass, add water, squeeze a lemon, add sugar, stir. Steps must be in the right order (sequence).
In block-based coding (like Scratch), we snap blocks to move a character: 'move 10 steps', 'turn 90°'. A loop repeats steps ('repeat 4 times: move, turn' draws a square). A condition makes choices ('if touching the wall, turn around').
When a program does not work, we debug: check each step, find the mistake and fix it.
A Class 4 student programs a sprite to draw a rangoli pattern by repeating 'move and turn' eight times.
✗ Computers understand what we mean even if instructions are unclear
✓ Computers follow instructions exactly; every step must be clear and in order.
🧪 Try this activity
Write instructions to guide a blindfolded classmate from the door to a desk using only 'step forward', 'turn left' and 'turn right'.
✍️ Question bank with answers
Tap an option to check multiple-choice answers. Open “Answer” or “Marking points” for the others.
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Repeating steps in a program is called a
Answer
C. loop
Loops repeat.
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To draw a square with 'move' and 'turn 90°', repeat
Answer
D. 4 times
A square has 4 sides.
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Finding and fixing mistakes in code is
Answer
D. debugging
Bugs are fixed by debugging.
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What is an algorithm?
Answer
step-by-step instructions to do a task
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Which block makes a choice?
Answer
an if (condition) block
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Put in order: 'eat', 'wash hands', 'serve food'.
Marking points
- wash hands
- serve food
- eat
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Write an algorithm for brushing your teeth with at least six steps.
Marking points
- Steps in a sensible order
- Includes picking brush, paste, brushing, rinsing, cleaning brush
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Your sprite should stop at the edge but walks off. What could be missing?
Answer
- A condition 'if touching edge, stop'
- Debug by testing each step
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Draw a flowchart for 'If it is raining, take an umbrella'.
Answer
- Start
- Decision diamond 'Raining?'
- Yes: take umbrella
- End
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