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# Intermediate Level

Programming

Chapter 6

#Chapter Profile
Introduction to Loops Conditions
Understanding Functions Cloning in Scratch
Designing Game

Take Off Century #Critical Thinking
21 st
Skills
State whether these statements are true or false.
1. Nesting means putting one thing inside another.
2. Constants can change their values during a program.

3. Variables store values that can change while a program runs.

In the previous chapter, you learnt about nesting, constants, variables, and loops using pseudocode. You
also used IF statements and problem-solving techniques. In this chapter, you'll build on that knowledge
to design and develop more Scratch scripts.

INTRODUCTION TO LOOPS

Sometimes, you need to repeat a task many times, either a set number of times or until something
happens. Loops help computers do the same task again and again without having to write the
instructions over and over. This saves time and makes coding easier.
For example, if your teacher asks you to clap your hands 10 times, you wouldn’t say “clap” and count
each clap out loud every time. Instead, you simply keep clapping until you have clapped 10 times.
So, the action “clap your hands” repeats 10 times — that’s how a loop works! You repeat something a
certain number of times. A loop in Scratch is a block that repeats an action many times without having
to write the same instructions again and again. Loops help us save time and make tasks easier by
avoiding repeated writing of the same instructions.

Simple Loops

There are two simple loops in Scratch:

repeat block: The repeat loop repeats a set number of times. You decide
how many times it repeats. For example, if you use repeat 10, the blocks

inside will run 10 times, like moving 10 steps 10 times.