diff --git a/Start/Ch 1/challenge.py b/Start/Ch 1/challenge.py
index 050cd6d..594e067 100644
--- a/Start/Ch 1/challenge.py	
+++ b/Start/Ch 1/challenge.py	
@@ -10,7 +10,13 @@
 # of "Ticker: Company -- $Price"
 
 class Stock:
-    pass
+    def __init__(self, ticker, price, company):
+        self.ticker = ticker
+        self.price = price
+        self.company = company
+
+    def get_description(self):
+        return f"{self.ticker}: {self.company} -- {self.price}"
 
 # ~~~~~~~~~ TEST CODE ~~~~~~~~~
 msft = Stock("MSFT", 342.0, "Microsoft Corp")
diff --git a/Start/Ch 2/challenge.py b/Start/Ch 2/challenge.py
index 556fd1f..32c0cdb 100644
--- a/Start/Ch 2/challenge.py	
+++ b/Start/Ch 2/challenge.py	
@@ -12,14 +12,32 @@
 # For stocks: "Ticker: Company -- $Price"
 # For bonds: "description: duration'yr' : $price : yieldamt%"
 
-class Asset():
-    pass
+class Asset(ABC):
+    def __init__(self, price):
+        self.price = price
 
-class Stock():
-    pass
+    @abstractmethod
+    def get_description(self):
+        pass
 
-class Bond():
-    pass
+class Stock(Asset):
+    def __init__(self, ticker, price, company_name):
+        super().__init__(price)
+        self.ticker = ticker
+        self.company_name = company_name
+
+    def get_description(self):
+        return f"{self.ticker}: {self.company_name} -- ${self.price}"
+
+class Bond(Asset):
+    def __init__(self, price, description, duration, yieldamt):
+        super().__init__(price)
+        self.description = description
+        self.duration = duration
+        self.yieldamt = yieldamt
+
+    def get_description(self):
+        return f"{self.description}: {self.duration}yr : ${self.price} : {self.yieldamt}%"
 
 
 # ~~~~~~~~~ TEST CODE ~~~~~~~~~
diff --git a/Start/Ch 3/challenge.py b/Start/Ch 3/challenge.py
index 679db2b..3bb6e99 100644
--- a/Start/Ch 3/challenge.py	
+++ b/Start/Ch 3/challenge.py	
@@ -23,6 +23,12 @@ def __init__(self, ticker, price, company):
         self.company = company
         self.ticker = ticker
 
+    def __str__(self):
+        return f"{self.ticker}: {self.company_name} -- ${self.price}"
+
+    def __lt__(self, other):
+        return self.price < other.price
+
 
 class Bond(Asset):
     def __init__(self, price, description, duration, yieldamt):
@@ -31,6 +37,12 @@ def __init__(self, price, description, duration, yieldamt):
         self.duration = duration
         self.yieldamt = yieldamt
 
+    def __str__(self):
+        return f"{self.description}: {self.duration}yr : ${self.price} : {self.yieldamt}%"
+
+    def __lt__(self, other):
+        return self.yieldamt < other.yieldamt
+
 
 # ~~~~~~~~~ TEST CODE ~~~~~~~~~
 stocks = [
diff --git a/Start/Ch 4/challenge.py b/Start/Ch 4/challenge.py
index f7634d0..022424a 100644
--- a/Start/Ch 4/challenge.py	
+++ b/Start/Ch 4/challenge.py	
@@ -4,32 +4,49 @@
 # Challenge: convert your classes to dataclasses
 # The subclasses are required to override the magic method
 # that makes them sortable
+from abc import ABC, abstractmethod
+from dataclasses import dataclass
 
-class Asset():
-    pass
-    
+from dataclasses import dataclass, field
 
+@dataclass
+class Asset(ABC):
+    price: float
+
+    @abstractmethod
+    def __lt__(self):
+        pass
+
+@dataclass
 class Stock(Asset):
-    pass
+    ticker: str
+    company: str
 
+    def __lt__(self, other):
+        return self.price < other.price
 
+@dataclass
 class Bond(Asset):
-    pass
+    description: str
+    duration: int
+    yieldamt: float
 
+    def __lt__(self, other):
+        return self.yieldamt < other.yieldamt
+        
 # ~~~~~~~~~ TEST CODE ~~~~~~~~~
 stocks = [
-    Stock("MSFT", 342.0, "Microsoft Corp"),
-    Stock("GOOG", 135.0, "Google Inc"),
-    Stock("META", 275.0, "Meta Platforms Inc"),
-    Stock("AMZN", 120.0, "Amazon Inc")
+    Stock(ticker="MSFT", price=342.0, company="Microsoft Corp"),
+    Stock(ticker="GOOG", price=135.0, company="Google Inc"),
+    Stock(ticker="META", price=275.0, company="Meta Platforms Inc"),
+    Stock(ticker="AMZN", price=120.0, company="Amazon Inc")
 ]
 
 bonds = [
-    Bond(95.31, "30 Year US Treasury", 30, 4.38),
-    Bond(96.70, "10 Year US Treasury", 10, 4.28),
-    Bond(98.65, "5 Year US Treasury", 5, 4.43),
-    Bond(99.57, "2 Year US Treasury", 2, 4.98)
-]
+    Bond(price=95.31, description="30 Year US Treasury", duration=30, yieldamt=4.38),
+    Bond(price=96.70, description="10 Year US Treasury", duration=10, yieldamt=4.28),
+    Bond(price=98.65, description="5 Year US Treasury", duration=5, yieldamt=4.43),
+    Bond(price=99.57, description="2 Year US Treasury", duration=2, yieldamt=4.98)
 
 try:
    ast = Asset(100.0)