Quest 1: Variables - Your Coding Backpack

Learn to Store and Use Information in Python

🎒 QUEST 1 | Difficulty: Beginner | Time: 5 minutes

📊 Complexity Level: Beginner ⭐

Perfect for students with no programming experience. This lesson introduces fundamental concepts that are essential for all programming. Great for college fair visitors and first-time coders!

💻 Interactive Options:

📓 Open in JupyterLite - Full Jupyter environment in your browser
▶️ Run code directly below - All code cells on this page are editable and runnable
📥 Download Notebook - For use in local Jupyter or Google Colab

📖 Introduction: The Adventurer’s Backpack

Imagine you’re an adventurer setting out on a journey. You have a magical backpack that can hold anything you need—water bottles, maps, treasure, even the number of monsters you’ve defeated! Each pocket in your backpack has a label, so you always know what’s inside.

In Python, variables are just like those labeled pockets in your backpack. They help you store information that you can use later in your program!

🗺️ Story Time: You’re starting your quest and need to track important information. You have 3 health points, your name is “Hero”, and you’ve collected 0 gold coins so far. How do you remember all this? With variables!

💡 Explanation: What are Variables?

A variable is a container that stores a value. Think of it as a labeled box: - The label is the variable name (like health) - The contents is the value (like 3)

In Python, creating a variable is super simple:

health = 3
player_name = "Hero"
gold = 0

That’s it! You just: 1. Choose a meaningful name 2. Use the = sign (we call this “assignment”) 3. Provide a value

📝 Key Rules for Variable Names:

✅ Good names: health, player_name, total_score - Use lowercase letters - Use underscores to separate words - Make them descriptive

❌ Bad names: x, asdf, 123name - Too short and unclear - Random letters - Can’t start with numbers

🎮 Activity: Create Your Character

Let’s create variables for your own game character! Try editing the code below to customize your character, then run it to see the results.

🎯 Challenge: Modify the code above to:

Change the character name to your own name
Set the level to 5
Give your character 200 health points
Change the magic power to 50

Then run the code to see your custom character!

👨‍💻 Code Example: Variables in Action

Variables become really powerful when you use them in calculations:

💡 Cool Trick: Instead of writing gold = gold + 25, you can use a shortcut: gold += 25. Both do the same thing!

🧩 Puzzle Time!

Figure out what this code will print before you run it:

🔑 Solution Explained:

The answer is:

x = 20
y = 10
z = 15

Why? When we calculated z = x + y, x was 5 and y was 10, so z became 15.

When we later changed x = 20, it didn’t change z! The variable z still holds the original calculation result. Variables don’t automatically update—you have to assign new values to them explicitly.

This is important: variables store values, not formulas!

🎯 Key Takeaways

✨ Quest 1 Complete! ✨

You’ve learned:

✅ Variables are labeled containers that store values
✅ Use the = sign to assign values to variables
✅ Variable names should be descriptive and follow naming rules
✅ You can update variables by assigning new values
✅ Variables store values, not formulas

Next Quest: Ready to learn about different types of data? Try Quest 2: Data Types!

🚀 Try This at Home!

Create variables for your favorite video game character or superhero. Track their name, power level, special abilities, and anything else you can think of. Practice makes perfect!

# Your turn! Create variables for your favorite character
favorite_hero = "Spider-Man"
power_level = 9000
can_fly = False
catchphrase = "With great power comes great responsibility"

# Add more and have fun!

📱 Share Your Progress! Completed Quest 1? Amazing! Move on to the next quest or try the challenge again with different values.

--- title: "Quest 1: Variables - Your Coding Backpack" subtitle: "Learn to Store and Use Information in Python" format: live-html: code-tools: true --- ::: {.quest-badge} 🎒 QUEST 1 | Difficulty: Beginner | Time: 5 minutes ::: ::: {.concept-box} **📊 Complexity Level: Beginner ⭐** Perfect for students with **no programming experience**. This lesson introduces fundamental concepts that are essential for all programming. Great for college fair visitors and first-time coders! ::: ::: {.tip-box} **💻 Interactive Options:** - 📓 **[Open in JupyterLite](../jupyterlite/lab/index.html?path=01-variables.ipynb)** - Full Jupyter environment in your browser - ▶️ **Run code directly below** - All code cells on this page are editable and runnable - 📥 **[Download Notebook](../files/lessons/01-variables.ipynb)** - For use in local Jupyter or Google Colab ::: ## 📖 Introduction: The Adventurer's Backpack Imagine you're an adventurer setting out on a journey. You have a magical backpack that can hold anything you need—water bottles, maps, treasure, even the number of monsters you've defeated! Each pocket in your backpack has a label, so you always know what's inside. In Python, **variables** are just like those labeled pockets in your backpack. They help you store information that you can use later in your program! ::: {.story-box} **🗺️ Story Time**: You're starting your quest and need to track important information. You have 3 health points, your name is "Hero", and you've collected 0 gold coins so far. How do you remember all this? With variables! ::: ## 💡 Explanation: What are Variables? A **variable** is a container that stores a value. Think of it as a labeled box: - The **label** is the variable name (like `health`) - The **contents** is the value (like `3`) In Python, creating a variable is super simple: ```python health = 3 player_name = "Hero" gold = 0 ``` That's it! You just: 1. Choose a meaningful name 2. Use the `=` sign (we call this "assignment") 3. Provide a value ::: {.concept-box} **📝 Key Rules for Variable Names:** ✅ **Good names**: `health`, `player_name`, `total_score` - Use lowercase letters - Use underscores to separate words - Make them descriptive ❌ **Bad names**: `x`, `asdf`, `123name` - Too short and unclear - Random letters - Can't start with numbers ::: ## 🎮 Activity: Create Your Character Let's create variables for your own game character! Try editing the code below to customize your character, then run it to see the results. ```{pyodide-python} # Create your character's stats character_name = "Robin" character_level = 1 health_points = 100 magic_power = 15 is_wizard = True # Display your character print("=== CHARACTER SHEET ===") print(f"Name: {character_name}") print(f"Level: {character_level}") print(f"Health: {health_points} HP") print(f"Magic: {magic_power} MP") print(f"Is Wizard: {is_wizard}") print("=" * 23) # Try changing these values! # What happens if you change health_points to 150? # What happens if you change is_wizard to False? ``` ::: {.challenge-box} **🎯 Challenge**: Modify the code above to: 1. Change the character name to your own name 2. Set the level to 5 3. Give your character 200 health points 4. Change the magic power to 50 Then run the code to see your custom character! ::: ## 👨‍💻 Code Example: Variables in Action Variables become really powerful when you use them in calculations: ```{pyodide-python} # Starting values gold = 10 enemies_defeated = 0 print(f"Starting gold: {gold}") print(f"Enemies defeated: {enemies_defeated}") print() # You found a treasure chest! gold = gold + 25 print("🎁 You found a treasure chest! +25 gold") print(f"Gold now: {gold}") print() # You defeated an enemy! enemies_defeated = enemies_defeated + 1 print("⚔️ You defeated an enemy!") print(f"Enemies defeated: {enemies_defeated}") print() # Another battle! enemies_defeated = enemies_defeated + 1 gold = gold + 5 print("⚔️ Another enemy defeated! +5 gold") print(f"Total enemies defeated: {enemies_defeated}") print(f"Total gold: {gold}") ``` ::: {.tip-box} **💡 Cool Trick**: Instead of writing `gold = gold + 25`, you can use a shortcut: `gold += 25`. Both do the same thing! ::: ## 🧩 Puzzle Time! Figure out what this code will print **before** you run it: ```{pyodide-python} # Can you predict the output? x = 5 y = 10 z = x + y x = 20 print(f"x = {x}") print(f"y = {y}") print(f"z = {z}") # Why is z still 15 and not 30? # Think about it, then run to check! ``` ::: {.solution-box} **🔑 Solution Explained**: The answer is: ``` x = 20 y = 10 z = 15 ``` **Why?** When we calculated `z = x + y`, x was 5 and y was 10, so z became 15. When we later changed `x = 20`, it **didn't** change z! The variable z still holds the original calculation result. Variables don't automatically update—you have to assign new values to them explicitly. This is important: **variables store values, not formulas**! ::: ## 🎯 Key Takeaways ::: {.quest-complete} ### ✨ Quest 1 Complete! ✨ You've learned: ✅ Variables are labeled containers that store values ✅ Use the `=` sign to assign values to variables ✅ Variable names should be descriptive and follow naming rules ✅ You can update variables by assigning new values ✅ Variables store values, not formulas **Next Quest**: Ready to learn about different types of data? Try [Quest 2: Data Types](02-data-types.qmd)! ::: ## 🚀 Try This at Home! Create variables for your favorite video game character or superhero. Track their name, power level, special abilities, and anything else you can think of. Practice makes perfect! ```python # Your turn! Create variables for your favorite character favorite_hero = "Spider-Man" power_level = 9000 can_fly = False catchphrase = "With great power comes great responsibility" # Add more and have fun! ``` --- ::: {.tip-box} **📱 Share Your Progress!** Completed Quest 1? Amazing! Move on to the next quest or try the challenge again with different values. :::