Computer Science
Grade 5
20 min
Calling Functions: Using Your Reusable Blocks
Students will learn how to call or execute functions in their programs.
What you'll learn
- Identify at least two different reasons why using functions (reusable blocks) can make coding easier and faster.
- Apply the concept of calling a function by successfully using a pre-defined function block in a coding activity to make a character perform a specific action.
- Explain, in your own words, what it means to 'call' a function and how it tells the computer to run the code inside that function.
- Solve a coding challenge by correctly using a function block multiple times to repeat a sequence of actions, demonstrating understanding of function reusability.
Tutorial Preview
1
Introduction & Learning Objectives
Learning Objectives
Define what a 'function call' is and how it executes a block of code.
Identify the function definition and the function call as separate parts of a program.
Explain why calling functions makes code shorter, more organized, and easier to read.
Predict the output of a program that calls the same function multiple times.
Write a program that calls pre-defined functions to solve a problem in the correct sequence.
Debug simple errors in function calls, such as spelling mistakes or missing parentheses.
Ever wish you could teach a robot a chore, give it a name like 'clean room', and then just say that one command to make it happen? 🤖 That's exactly what calling a function does in coding!
In this lesson, you'll learn the superpower...
2
Key Concepts & Vocabulary
TermDefinitionExample
FunctionA named block of code that performs a specific task. Think of it as a recipe with a name.A function named `drawStar` that contains all the `move` and `turn` commands needed to draw a star shape.
Function DefinitionThe part of the code where you create the function. You give it a name and write the step-by-step instructions inside it.The block of code that starts with `function drawStar() { ... }` and contains the drawing commands inside the curly braces.
Function CallA single line of code that tells the program to run the instructions inside a function.Typing `drawStar();` in your main program, which tells the computer to find the `drawStar` recipe and follow its instructions.
ReuseThe power to use a function many times in your program without having to copy...
3
Core Syntax & Patterns
The Calling Syntax
functionName()
To run, or 'call', a function, you must type its exact name followed by parentheses. The name is case-sensitive, so `myFunction` is different from `myfunction`.
Define Before You Call
A function must be defined before your program tries to call it.
The computer needs to know the instructions for a function *before* you ask it to perform them. It's best to put all your function definitions at the top of your program.
The 'Jump and Return' Flow
Main Program -> Function Call -> Jumps to Function Code -> Runs Function -> Returns to Main Program
Think of a function call as a side quest in a game. Your program pauses its main path, completes the side quest (the function), and then returns to the exact s...
4 more steps in this tutorial
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Challenging
Your program is supposed to draw a fence `|-|` but instead it draws `_-_`. Your code is below. Which function's DEFINITION is most likely broken?
`function drawFencePost() { ... }`
`function drawHorizontalLine() { ... }`
`drawFencePost();`
`drawHorizontalLine();`
`drawFencePost();`
A.The `drawHorizontalLine()` function is fine, but the `drawFencePost()` function is broken.
B.Both function definitions are broken.
C.The `drawFencePost()` function is fine, but the `drawHorizontalLine()` function is broken.
D.The function calls are in the wrong order.
Challenging
You have `drawStar()` which prints '*' and `drawDash()` which prints '-'. You want to create the pattern '*-*-*'. Which code block correctly produces this pattern?
A.`for (let i = 0; i < 2; i++) { drawStar(); drawDash(); } drawStar();`
B.`for (let i = 0; i < 3; i++) { drawStar(); drawDash(); }`
C.`drawStar(); for (let i = 0; i < 2; i++) { drawDash(); drawStar(); }`
D.`for (let i = 0; i < 5; i++) { drawStar(); }`
Challenging
A student's code `PrintMessage()` isn't working. The function is defined as `function printMessage()`. The student says, 'It must be broken because the computer doesn't know what a message is.' What is the flaw in the student's reasoning?
A.The student is correct; the computer doesn't understand English words.
B.The student forgot to put quotes around the function name.
C.The student should have named the function `function_print_message()`.
D.The student is ignoring the actual error, which is a case-sensitivity mismatch, not the meaning of the words.
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Calling Functions: Using Your Reusable Blocks is a Grade 5 Computer Science lesson on ExcelOS.
What will I learn in Calling Functions: Using Your Reusable Blocks?
You'll be able to: Identify at least two different reasons why using functions (reusable blocks) can make coding easier and faster; Apply the concept of calling a function by successfully using a pre-defined function block in a coding activity to….
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How many practice questions are included with Calling Functions: Using Your Reusable Blocks?
This lesson includes 43 practice questions across multiple difficulty levels, each with instant feedback and explanations.