diff --git a/challenges/01-calc.py b/challenges/01-calc.py
index 87f5190..2a2cfa1 100644
--- a/challenges/01-calc.py
+++ b/challenges/01-calc.py
@@ -2,3 +2,65 @@
 # input() always returns a string value. If you ever want someone
 # to enter a number you have to use the `int()` function to convert
 # what they typed in to a string.
+
+is_running = True
+
+while is_running:
+    # display math choices and ask user to chose one
+    prompt = ">"
+    print("Hello, User🙋‍♂️")
+    print("Tell me what kind of math you would like to do")
+    print("possible choices: add, sub, mul, div")
+    math_choice = input(prompt)
+    print(f"math choice: {math_choice}")
+
+
+    # ask the user to input two numbers
+    print ("Excellent math choice! Enter the first number to use")
+    number_one = input(prompt)
+    print("Now, enter a second Number")
+    number_two = input(prompt)
+
+    try:
+    # convert input to integers
+      number_one = int(number_one)
+      number_two = int(number_two)
+
+        # if/elif/else
+      # og dictionary switch
+      switch = {
+        "add": number_one + number_two,
+        "sub": number_one - number_two,
+        "mul": number_one * number_two,
+        "div": number_one / number_two
+      }
+
+      if math_choice in switch:
+        print(f"result: {switch[math_choice]}")
+      else:
+        #  defualt for the switch case
+        print(f"I lied, {math_choice} isn't a math I know about")
+
+      # match case (new python switch)
+      match math_choice:
+         case "add":
+            print(f"{number_one} + {number_two} = {number_one + number_two}")
+         case "sub":
+            print(f"{number_one} - {number_two} = {number_one - number_two}")
+         case "mul":
+            print(f"{number_one} * {number_two} = {number_one * number_two}")
+         case "div":
+            print(f"{number_one} / {number_two} = {number_one / number_two}")
+         case _:
+            print(f"{number_one} makes no sense to me! ")
+            
+    except ValueError as e:
+      #  handle error instead of crashing
+       print("That wasn't a real number!")
+
+
+    # ask the user if they would like to exit
+    print("would you like to contine doin math with me [y/n]?")
+    should_quit = input(prompt)
+    if should_quit == "n":
+       is_running = False
\ No newline at end of file
diff --git a/challenges/02-reverse.py b/challenges/02-reverse.py
index 8cf2677..f40aba2 100644
--- a/challenges/02-reverse.py
+++ b/challenges/02-reverse.py
@@ -6,3 +6,15 @@
 # several ways to reverse a string, and it's a good read!
 #
 # http://www.techbeamers.com/essential-python-tips-tricks-programmers/?utm_source=mybridge&utm_medium=blog&utm_campaign=read_more#tip1
+
+string = "Hello"
+
+reversed_string = reversed(string)
+new_string = ""
+for letter in reversed(string):
+    new_string =+ letter
+
+print(new_string)
+
+
+# print("".join(reversed(string)))
\ No newline at end of file
diff --git a/challenges/03-bank.py b/challenges/03-bank.py
index 554cb1d..d147124 100644
--- a/challenges/03-bank.py
+++ b/challenges/03-bank.py
@@ -1,3 +1,49 @@
 print("Welcome to Chase bank.")
 print("Have a nice day!")
 
+class BankAccount:
+    def __init__(self):
+        self.balance = 0
+
+    def deposit(self, amount):
+        self.balance += amount
+        return self.balance
+
+    def withdraw(self, amount):
+        if amount > self.balance:
+            print("Insufficient balance!")
+            return self.balance
+        else:
+            self.balance -= amount
+            return self.balance
+
+    def check_balance(self):
+        return self.balance
+
+
+def main():
+    account = BankAccount()
+    
+    while True:
+        print(f"Your current balance is\n{account.check_balance()}")
+        action = input("What would you like to do? (deposit, withdraw, check_balance)\n")
+        
+        if action.lower() == "deposit":
+            amount = float(input("How much would you like to deposit?\n"))
+            account.deposit(amount)
+        elif action.lower() == "withdraw":
+            amount = float(input("How much would you like to withdraw?\n"))
+            account.withdraw(amount)
+        elif action.lower() == "check_balance":
+            pass
+        else:
+            print("Invalid action. Please enter 'deposit', 'withdraw' or 'check_balance'.")
+
+        done = input("Are you done? (yes/no)\n")
+        if done.lower() == 'yes':
+            print("Thank you!")
+            break
+
+
+if __name__ == "__main__":
+    main()
diff --git a/challenges/04-alphabetical.py b/challenges/04-alphabetical.py
index 5051ec4..23a8bdb 100644
--- a/challenges/04-alphabetical.py
+++ b/challenges/04-alphabetical.py
@@ -1,3 +1,22 @@
 # You'll need to use a couple of built in functions to alphabetize a string. 
 # Try to avoid looking up the exact answer and look at built in functions for
 # lists and strings instead.
+
+
+# convert to lsit approch
+string = "sjndgnsndflafdkjsngnsdffgh"
+string_list = list(string)
+string_list.sort()
+string = "".join(string_list)
+print(string)
+
+# sorted function approach
+print("".join(sorted(string)))
+
+
+# python slice syntax
+my_list = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
+# [slice start (default 0): slice end(deflaut 0): step (defualt 1)]
+my_list_copy = my_list[::] # make a copy with defaults 
+# print(my_list[::2]) # increments by 2's
+# print(my_list[::-1]) # reverses the list