BBP Activity 7: Python Function Exercises

:video_game: Activity Time!

Time needed: 45-60 minutes
What you'll create: Three awesome programs using functions - a rectangle calculator, a bank account tracker, and a multiplication machine!

Before You Start:

Check that you have:

• Your computer ready with internet
• Your Google account for logging into EduBlocks
• Read through Lesson 7 about functions
• A quiet workspace to focus

Getting Started with EduBlocks

1. Open EduBlocks and login with your Google account: https://app.edublocks.org/login

2. Create a new project:

   • Click on the "Editor" icon for new projects
   • Click on the "Projects" icon to continue previous work

3. Set up each exercise:

   • Select Python 3 mode
   • Name your project clearly (Example: "Exercise Function 1")
   • Click "Start Coding" button
   • Click "Save" at the top-right corner

:bulb: :bulb: Pro tip: Save your work every 5-10 minutes! Press the Save button regularly to keep your progress safe.

Important: Keep all three exercise tabs open - you'll need the share links for submission!

Your Three Function Challenges

:emoji: Exercise One: Rectangle Area Calculator

Time: 15 minutes

Let's build a smart calculator that finds the area of any rectangle!

What you'll learn: How to create functions with parameters (inputs)

Steps to build:

1. Drag the def function block from the Functions category
   • Name your function: area
   • Add 2 parameters: width and height
2. Inside your function, create a variable:
   • Drag a variable block and name it result
   • Set it to: width * height
3. Add a print statement inside the function:
   • Print: "Total area of rectangle: " + str(result)
4. Outside the function, add input blocks:
   • First input: "Width: "
   • Second input: "Height: "
5. Call your function:
   • Drag the function call block
   • Pass both input values to your area functiontip :emoji: Stuck? Remember that parameters are like empty boxes that get filled when you call the function. Your width and height parameters will receive the values from your inputs!

:emoji: Exercise 2: Bank Account Tracker

Time: 20 minutes

Create your own digital piggy bank that tracks money coming in and going out!

What you'll learn: How to use global variables in functions

Steps to build:

1. Create your starting balance:

   • Drag a variable block: name it balance
   • Set value to 500
   • Add a print block to show: "Balance: " + str(balance)

2. Build the income function:

   • Drag a def block and name it income
   • Add one parameter: increment
   • Inside the function:
     • First line: Drag the global block and type balance
     • Second line: Use the += operator block to add increment to balance
     • Third line: Print "Income: " + str(increment)
     • Fourth line: Print "Balance: " + str(balance)

3. Build the expense function:

   • Drag another def block and name it expense
   • Add one parameter: decrement
   • Inside the function:
     • First line: Drag the global block and type balance
     • Second line: Use the -= operator block to subtract decrement from balance
     • Third line: Print "Expense: " + str(decrement)
     • Fourth line: Print "Balance: " + str(balance)

4. Test your bank account:

   • Call income(300) - You earned $300!
   • Call expense(200) - You spent $200
   • Call income(150) - More money coming in!
   • Call expense(135) - Another expense

:bulb: :bulb: Why use global? The global keyword tells Python that you want to change the balance variable that exists outside the function. Without it, Python would create a new variable inside the function!

:emoji:️ Exercise 3: Multiplication Machine

Time: 20 minutes

Build a super-fast multiplication calculator that shows times tables!

What you'll learn: How functions can return values

Steps to build:

1. Create the x2 function (multiply by 2):
   • Drag a def block and name it x2
   • Add one parameter: n
   • Inside: Add a return block with str(n * 2)
2. Create the x3 function (multiply by 3):
   • Drag another def block and name it x3
   • Add one parameter: n
   • Inside: Add a return block with str(n * 3)
3. Create the x4 function (multiply by 4):
   • Drag another def block and name it x4
   • Add one parameter: n
   • Inside: Add a return block with str(n * 4)
4. Get user input:
   • Create a variable n
   • Set it to: int(input("Number: "))
5. Display the multiplication results:
   • Print: str(n) + " x 2 = " + x2(n)
   • Print: str(n) + " x 3 = " + x3(n)
   • Print: str(n) + " x 4 = " + x4(n)tip :dart: Return vs Print: The return block sends a value back from the function, which you can then use in your print statements. It's like the function is answering a question!

Test your calculator with different numbers!

:dart: Troubleshooting Tips

Common issues and fixes:

1. "Function not defined" error?

   • Make sure you define the function BEFORE calling it
   • Check that your function name spelling matches exactly

2. Global variable not changing?

   • Did you remember to add the global keyword inside your function?
   • The global block must be the first line inside the function

3. Getting weird output?

   • Check that you're using str() to convert numbers to text
   • Make sure your + signs connect text properly

4. Input not working?

   • Remember to convert input to int() for numbers
   • The conversion blocks should wrap around the input block

:trophy: Challenge Yourself!

Once you finish all three exercises, try these bonus challenges:

1. Rectangle Challenge: Modify Exercise 1 to also calculate the perimeter (distance around the rectangle). Formula: 2 * (width + height)

2. Bank Challenge: Add a new function called check_balance() that just prints the current balance without changing it

3. Calculator Challenge: Create a new function x10 that multiplies by 10 and add it to your calculator

4. Super Challenge: Can you create a function that calls another function? Try making a double_income() function that calls your income() function twice!

:books: What You've Learned

After completing these exercises, you now know how to:

• Create functions with the def block
• Use parameters to pass information into functions
• Work with global variables using the global keyword
• Return values from functions
• Call functions with different arguments

Real Python Connection: In text-based Python, functions work exactly the same way! You're learning real programming concepts through visual blocks.

:emoji: Project Submission

Ready to submit? Make sure you have:

• :white_check_mark: Completed all three exercises
• :white_check_mark: Tested each program with different inputs
• :white_check_mark: Saved all three projects in EduBlocks
• :white_check_mark: Got the share link for each project

Submit Your Project Here

Remember: You need to submit 3 project links - one for each exercise!

:bulb: Tip

:star2: Final tip: Functions are like recipes - they take ingredients (parameters), follow steps (function body), and sometimes give you back a result (return value). You're now a function chef!