Topic: Student Grade Calculator

Description: This program prompts a user to input a student's marks for five individual subjects. It automatically computes the total marks, evaluates the overall percentage, and uses conditional statements to assign a final corresponding letter grade.

Why: Building a grade calculator teaches students how to collect multiple numerical inputs, utilize accumulator variables to find aggregates, perform basic division arithmetic for percentages, and use a multi-tiered if-elif-else structure to map numerical results to qualitative metrics.

Program Code

Copy and run the following Python code to see the grade calculator in action:

def calculate_student_grade():
    print("=============================")
    print("   STUDENT GRADE CALCULATOR  ")
    print("=============================")
    
    # Collecting scores for 5 subjects
    try:
        sub1 = float(input("Enter marks for Subject 1 (0-100): "))
        sub2 = float(input("Enter marks for Subject 2 (0-100): "))
        sub3 = float(input("Enter marks for Subject 3 (0-100): "))
        sub4 = float(input("Enter marks for Subject 4 (0-100): "))
        sub5 = float(input("Enter marks for Subject 5 (0-100): "))
    except ValueError:
        print("\nError: Please enter valid numbers for marks.")
        return

    # Calculate Total and Percentage
    total_marks = sub1 + sub2 + sub3 + sub4 + sub5
    percentage = (total_marks / 500) * 100
    
    # Determine Grade using Multi-tier Conditional Statements
    if percentage >= 90:
        grade = "A+"
        status = "Passed with Distinction"
    elif percentage >= 80:
        grade = "A"
        status = "Passed"
    elif percentage >= 70:
        grade = "B"
        status = "Passed"
    elif percentage >= 60:
        grade = "C"
        status = "Passed"
    elif percentage >= 50:
        grade = "D"
        status = "Passed"
    else:
        grade = "F"
        status = "Failed"
        
    # Output Results Summary
    print("\n-----------------------------")
    print("       RESULTS SUMMARY        ")
    print("-----------------------------")
    print(f"Total Marks Obtained : {total_marks:.2f} / 500.00")
    print(f"Aggregate Percentage : {percentage:.2f}%")
    print(f"Assigned Grade       : {grade}")
    print(f"Academic Status      : {status}")
    print("-----------------------------")

# Execute the program
calculate_student_grade()

Expected Console Output Examples

Example 1 (High Performing Profile):

=============================
   STUDENT GRADE CALCULATOR  
=============================
Enter marks for Subject 1 (0-100): 88
Enter marks for Subject 2 (0-100): 92.5
Enter marks for Subject 3 (0-100): 79
Enter marks for Subject 4 (0-100): 85
Enter marks for Subject 5 (0-100): 94

-----------------------------
       RESULTS SUMMARY        
-----------------------------
Total Marks Obtained : 438.50 / 500.00
Aggregate Percentage : 87.70%
Assigned Grade       : A
Academic Status      : Passed
-----------------------------

Example 2 (Failing Profile):

Enter marks for Subject 1 (0-100): 45
Enter marks for Subject 2 (0-100): 38
Enter marks for Subject 3 (0-100): 52
Enter marks for Subject 4 (0-100): 41
Enter marks for Subject 5 (0-100): 47

-----------------------------
       RESULTS SUMMARY        
-----------------------------
Total Marks Obtained : 223.00 / 500.00
Aggregate Percentage : 44.60%
Assigned Grade       : F
Academic Status      : Failed
-----------------------------

Core Syntax & Concept Breakdown

• Exception Handling (try-except): The input capture is wrapped in a try block. If a student inputs text instead of a number (e.g., typing "eighty"), the program catches the ValueError and safely stops without throwing a fatal crash.
• Sequential Evaluation: Python parses the conditional checks from top to bottom. If a percentage is 87.70%, it evaluates false for the >= 90 check, updates true for the >= 80 check, applies the grade, and exits the structural block immediately.
• F-String Formatting (:.2f): Ensures that any calculated outputs containing extended trailing decimal loops are rounded off cleanly to two places for standard report representation.