diff --git a/FunProjects/Grades.py b/FunProjects/Grades.py
index 21ae916..8070efe 100644
--- a/FunProjects/Grades.py
+++ b/FunProjects/Grades.py
@@ -3,16 +3,22 @@ def __init__(self):
         self.grades = {}
 
     def add_grade(self, student, grade):
-        self.grades[student] = grade
-        print(student,"Grade is ",self.grades[student])
+        if isinstance(grade, (int, float)):
+            self.grades[student] = grade
+            print(student, "Grade is", self.grades[student])
+        else:
+            print(f"Invalid grade for {student}. Grade must be a number.")
+
     def calculate_average(self):
+        if not self.grades:
+            return 0  # Avoid division by zero
         total = sum(self.grades.values())
         average = total / len(self.grades)
         return average
 
-# Example Usage
+# Example Usage !
 grades = StudentGrades()
 grades.add_grade("John", 85)
 grades.add_grade("Sarah", 90)
 grades.add_grade("Mike", 78)
-print("Average grade:", grades.calculate_average())  
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+print("Average grade:", grades.calculate_average())
diff --git a/problems/easy/easy_q13.py b/problems/easy/easy_q13.py
index dd23d02..1370cfa 100644
--- a/problems/easy/easy_q13.py
+++ b/problems/easy/easy_q13.py
@@ -1,6 +1,5 @@
-# Month Name: Write a program that takes a number (1-12) and prints the corresponding month name using a switch case.
 def month_name(month):
-    switch = {
+    months = {
         1: "January",
         2: "February",
         3: "March",
@@ -14,12 +13,14 @@ def month_name(month):
         11: "November",
         12: "December"
     }
- 
-    return switch.get(month)   
+
+    return months.get(month, "Invalid month number")
+
 if __name__ == "__main__":
-    chooseMonthNum = int(input("Enter the Month from 1 to 12: "))
- 
- 
-    return switch.get(month, "Invalid Month")
+    try:
+        chooseMonthNum = int(input("Enter the Month from 1 to 12: "))
+        print("Month is:", month_name(chooseMonthNum))
+    except ValueError:
+        print("Invalid input. Please enter a number.")
  
  
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diff --git a/problems/easy/easy_q14.py b/problems/easy/easy_q14.py
index 8f09e9d..5ff0ec9 100644
--- a/problems/easy/easy_q14.py
+++ b/problems/easy/easy_q14.py
@@ -1,29 +1,18 @@
-# Vowel or Consonant: Accept a character and use a switch case to determine if it is a vowel or a consonant.
 def vowel_or_consonant(char):
-    char=char.lower()
-    switch = {
-        'a': "Vowel",
-        'e': "Vowel",
-        'i': "Vowel",
-        'o': "Vowel",
-        'u': "Vowel",
-        'A': "Vowel",
-        'E': "Vowel",
-        'I': "Vowel",
-        'O': "Vowel",
-        'U': "Vowel",
-    }
- 
-    if char in switch:
-        return "Vowels" 
+    char = char.lower()
+    vowels = {'a', 'e', 'i', 'o', 'u'}
+
+    if len(char) != 1 or not char.isalpha():
+        return "Invalid input. Please enter a single alphabet letter."
+
+    if char in vowels:
+        return "Vowel"
     else:
         return "Consonant"
+
 if __name__ == "__main__":
-    characterInput  = input("Enter the character : ")
- 
-    return switch.get(char)
+    characterInput = input("Enter a single alphabet character: ")
+    result = vowel_or_consonant(characterInput)
+    print("Result:", result)
 
- 
- 
-    return switch.get(char, "constant")   
- 
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+    
\ No newline at end of file
diff --git a/problems/easy/easy_q15.py b/problems/easy/easy_q15.py
index 09bbf29..a91c636 100644
--- a/problems/easy/easy_q15.py
+++ b/problems/easy/easy_q15.py
@@ -1,31 +1,17 @@
  
-# Grade Description: Write a program that accepts a grade (A, B, C, D, F) and prints its description (e.g., A = Excellent, B = Good, etc.) using a switch case.
 def grade_description(grade):
     switch = {
- 
         'A': "Excellent",
         'B': "Good",
         'C': "Average",
-        'D': "Poor",  
-        'B': "Good",
-        'C': "Average",
         'D': "Poor",
-        'A': "Excellent",  
- 
         'F': "Fail"
- 
- 
     }
- 
-    return switch.get(grade, "Not a valid grade") 
+    return switch.get(grade, "Not a valid grade")
 
 if __name__ == "__main__":
- 
-    user = input("Enter grade among A,B,C,D,F *in captial:")
-    rs = grade_description(user)
- 
-    alp = input("Enter a grade: ").upper()
-    rs = grade_description(alp)
- 
-    print(rs)
+    grade_input = input("Enter a grade (A, B, C, D, F) in capital letters: ").upper()
+    result = grade_description(grade_input)
+    print(result)
+
   
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