diff --git a/lib/account.rb b/lib/account.rb
index e69de29b..882337c6 100644
--- a/lib/account.rb
+++ b/lib/account.rb
@@ -0,0 +1,55 @@
+require 'csv'
+
+module Bank
+  class Account
+    attr_reader :id, :balance, :open_date
+    def initialize(id, balance, open_date = "")
+      raise ArgumentError.new("balance must be >= 0") if balance < 0
+
+      @id = id
+      @balance = balance
+      @open_date = open_date
+    end
+
+    def withdraw(amount)
+      balance_min = 0
+      withdraw_internal(amount, balance_min)
+    end
+
+    def deposit(amount)
+      raise ArgumentError.new("deposit must be > 0") if amount <= 0
+      @balance += amount
+    end
+
+    def self.all
+      accounts = []
+      CSV.open("support/accounts.csv").each do |line|
+        accounts << self.new(line[0].to_f/100, line[1].to_f/100, line[2])
+      end
+      return accounts
+    end
+
+    def self.find(id)
+      self.all.each do |account|
+        return account if account.id == id
+      end
+      raise ArgumentError.new("ID does not exist")
+    end
+
+    private
+    
+    def withdraw_internal(amount, balance_min)
+      raise ArgumentError.new("withdrawl must be > 0") if amount <= 0
+      if update_balance?(amount, balance_min)
+        @balance -= amount
+      end
+      return @balance
+    end
+
+    def update_balance?(amount, balance_min)
+      return true if @balance - amount >= balance_min
+      puts "Requested withdrawl amount surpasses allowable account balance."
+      return false
+    end
+  end
+end
diff --git a/lib/checking_account.rb b/lib/checking_account.rb
new file mode 100644
index 00000000..86bc9c71
--- /dev/null
+++ b/lib/checking_account.rb
@@ -0,0 +1,35 @@
+require_relative 'account'
+
+module Bank
+  class CheckingAccount < Account
+    def initialize(id, balance)
+      super(id, balance)
+      @number_of_checks = 0 #free_checks = 3
+    end
+
+    def withdraw(amount)
+      fee = 1.0
+      balance_min = 0
+      withdraw_internal(amount + fee, balance_min)
+    end
+
+    def withdraw_using_check(amount)
+      if @number_of_checks >= 3
+        fee = 2.0
+      else
+        fee = 0
+      end
+      balance_min = -10.0
+
+      if update_balance?((amount + fee), balance_min)
+        @number_of_checks += 1
+      end
+
+      withdraw_internal(amount + fee, balance_min)
+    end
+
+    def reset_checks
+      @number_of_checks = 0
+    end
+  end
+end
diff --git a/lib/savings_account.rb b/lib/savings_account.rb
new file mode 100644
index 00000000..ca5f4ce4
--- /dev/null
+++ b/lib/savings_account.rb
@@ -0,0 +1,24 @@
+require_relative 'account'
+
+module Bank
+  class SavingsAccount < Account
+    def initialize(id, balance)
+      # Account must have a minimum balance of $10
+      raise ArgumentError.new("balance must be >= 10") if balance < 10
+      super(id, balance)
+    end
+
+    def withdraw(amount)
+      fee = 2.0
+      balance_min = 10.0
+      withdraw_internal(amount + fee, balance_min)
+    end
+
+    def add_interest(rate) #input rate is assumed a percentage
+      raise ArgumentError.new("interest rate must be positive") if rate <= 0
+      interest = @balance * rate / 100
+      @balance +=interest
+      return interest
+    end
+  end
+end
diff --git a/specs/account_spec.rb b/specs/account_spec.rb
index 6c399139..475084fc 100644
--- a/specs/account_spec.rb
+++ b/specs/account_spec.rb
@@ -2,6 +2,7 @@
 require 'minitest/reporters'
 require 'minitest/skip_dsl'
 require_relative '../lib/account'
+require 'csv'
 
 describe "Wave 1" do
   describe "Account#initialize" do
@@ -18,10 +19,6 @@
     end
 
     it "Raises an ArgumentError when created with a negative balance" do
-      # Note: we haven't talked about procs yet. You can think
-      # of them like blocks that sit by themselves.
-      # This code checks that, when the proc is executed, it
-      # raises an ArgumentError.
       proc {
         Bank::Account.new(1337, -100.0)
       }.must_raise ArgumentError
@@ -67,7 +64,7 @@
       # anything at all is printed out the test will pass.
       proc {
         account.withdraw(withdrawal_amount)
-      }.must_output /.+/
+      }.must_output (/.+/)
     end
 
     it "Doesn't modify the balance if the account would go negative" do
@@ -137,35 +134,74 @@
 end
 
 # TODO: change 'xdescribe' to 'describe' to run these tests
-xdescribe "Wave 2" do
+describe "Wave 2" do
   describe "Account.all" do
-    it "Returns an array of all accounts" do
-      # TODO: Your test code here!
-      # Useful checks might include:
-      #   - Account.all returns an array
-      #   - Everything in the array is an Account
-      #   - The number of accounts is correct
-      #   - The ID and balance of the first and last
-      #       accounts match what's in the CSV file
-      # Feel free to split this into multiple tests if needed
+    it "Returns an array" do
+      accounts = Bank::Account.all
+      accounts.must_be_instance_of Array
+    end
+
+    it "Contains only Account elements in the returned array" do
+      accounts = Bank::Account.all
+      # Check that each element within the array is an instance of the Account class
+      accounts.each do |account|
+        account.must_be_instance_of Bank::Account
+      end
+    end
+
+    it "Includes the correct number of accounts in the returned array" do
+      accounts = Bank::Account.all
+      num_of_accounts = CSV.read("support/accounts.csv").size
+      accounts.length.must_equal num_of_accounts
+    end
+
+    it "Creates a first account with the csv's first listed ID and balance" do
+      first_id = CSV.read("support/accounts.csv").first[0].to_f/100
+      first_balance = CSV.read("support/accounts.csv").first[1].to_f/100
+      accounts = Bank::Account.all
+
+      accounts.first.id.must_equal first_id
+      accounts.first.balance.must_equal first_balance
+    end
+
+    it "Creates a last account with the csv's last listed ID and balance" do
+      last_id = CSV.read("support/accounts.csv").last[0].to_f/100
+      last_balance = CSV.read("support/accounts.csv").last[1].to_f/100
+      accounts = Bank::Account.all
+
+      accounts.last.id.must_equal last_id
+      accounts.last.balance.must_equal last_balance
     end
   end
 
   describe "Account.find" do
+    def find_and_verify_account(id)
+      account = Bank::Account.find(id)
+      account.must_be_instance_of Bank::Account
+      account.id.must_equal id
+    end
+
     it "Returns an account that exists" do
-      # TODO: Your test code here!
+      seventh_id = CSV.read("support/accounts.csv")[6][0].to_f/100
+      find_and_verify_account(seventh_id)
     end
 
     it "Can find the first account from the CSV" do
-      # TODO: Your test code here!
+      first_id = CSV.read("support/accounts.csv").first[0].to_f/100
+      find_and_verify_account(first_id)
     end
 
     it "Can find the last account from the CSV" do
-      # TODO: Your test code here!
+      last_id = CSV.read("support/accounts.csv").last[0].to_f/100
+      find_and_verify_account(last_id)
     end
 
     it "Raises an error for an account that doesn't exist" do
-      # TODO: Your test code here!
+      fake_id = 80
+
+      proc {
+        Bank::Account.find(fake_id)
+      }.must_raise ArgumentError
     end
   end
 end
diff --git a/specs/checking_account_spec.rb b/specs/checking_account_spec.rb
index 7f95339e..2f89ff0a 100644
--- a/specs/checking_account_spec.rb
+++ b/specs/checking_account_spec.rb
@@ -1,17 +1,9 @@
 require 'minitest/autorun'
 require 'minitest/reporters'
 require 'minitest/skip_dsl'
+require_relative '../lib/checking_account'
 
-# TODO: uncomment the next line once you start wave 3 and add lib/checking_account.rb
-# require_relative '../lib/checking_account'
-
-# Because a CheckingAccount is a kind
-# of Account, and we've already tested a bunch of functionality
-# on Account, we effectively get all that testing for free!
-# Here we'll only test things that are different.
-
-# TODO: change 'xdescribe' to 'describe' to run these tests
-xdescribe "CheckingAccount" do
+describe "CheckingAccount" do
   describe "#initialize" do
     # Check that a CheckingAccount is in fact a kind of account
     it "Is a kind of Account" do
@@ -22,59 +14,170 @@
 
   describe "#withdraw" do
     it "Applies a $1 fee each time" do
-      # TODO: Your test code here!
+      start_balance = 100.0
+      withdrawal_amount = 25.0
+      fee = 1.0
+      account = Bank::CheckingAccount.new(12345, start_balance)
+
+      updated_balance = account.withdraw(withdrawal_amount)
+      expected_balance = start_balance - withdrawal_amount - fee
+
+      # Both the value returned and the balance in the account
+      # should apply the fee
+      updated_balance.must_equal expected_balance
+      account.balance.must_equal expected_balance
     end
 
     it "Doesn't modify the balance if the fee would put it negative" do
-      # TODO: Your test code here!
+      start_balance = 100.0
+      withdrawal_amount = 100.0 # + $1 fee
+      account = Bank::CheckingAccount.new(12345, start_balance)
+
+      updated_balance = account.withdraw(withdrawal_amount)
+
+      # Both the value returned and the balance in the account
+      # must be un-modified.
+      updated_balance.must_equal start_balance
+      account.balance.must_equal start_balance
     end
   end
 
   describe "#withdraw_using_check" do
     it "Reduces the balance" do
-      # TODO: Your test code here!
+      # Add for possible check fee here or assume brand new account?
+      start_balance = 100.0
+      withdrawal_amount = 25.0
+      account = Bank::CheckingAccount.new(12345, start_balance)
+
+      account.withdraw_using_check(withdrawal_amount)
+      expected_balance = start_balance - withdrawal_amount
+
+      account.balance.must_equal expected_balance
     end
 
     it "Returns the modified balance" do
-      # TODO: Your test code here!
+      start_balance = 100.0
+      withdrawal_amount = 25.0
+      account = Bank::CheckingAccount.new(12345, start_balance)
+
+      updated_balance = account.withdraw_using_check(withdrawal_amount)
+      expected_balance = start_balance - withdrawal_amount
+
+      updated_balance.must_equal expected_balance
     end
 
     it "Allows the balance to go down to -$10" do
-      # TODO: Your test code here!
+      account = Bank::CheckingAccount.new(12345, 100.0)
+      updated_balance = account.withdraw_using_check(account.balance + 10.0)
+
+      updated_balance.must_equal (-10)
+      account.balance.must_equal (-10)
     end
 
     it "Outputs a warning if the account would go below -$10" do
-      # TODO: Your test code here!
+      start_balance = 100.0
+      withdrawal_amount = 200.0
+      account = Bank::CheckingAccount.new(12345, start_balance)
+
+      # Anything printed to the console output will pass the test
+      proc {
+        account.withdraw_using_check(withdrawal_amount)
+      }.must_output (/.+/)
     end
 
     it "Doesn't modify the balance if the account would go below -$10" do
-      # TODO: Your test code here!
+      start_balance = 100.0
+      withdrawal_amount = 200.0
+      account = Bank::CheckingAccount.new(12345, start_balance)
+
+      updated_balance = account.withdraw_using_check(withdrawal_amount)
+
+      # Both the value returned and the balance in the account
+      # must be un-modified.
+      updated_balance.must_equal start_balance
+      account.balance.must_equal start_balance
     end
 
     it "Requires a positive withdrawal amount" do
-      # TODO: Your test code here!
+      withdrawal_amount = -25.0
+      account = Bank::CheckingAccount.new(12345, 100.0)
+
+      proc {
+        account.withdraw_using_check(withdrawal_amount)
+      }.must_raise ArgumentError
     end
 
     it "Allows 3 free uses" do
-      # TODO: Your test code here!
+      start_balance = 100.0
+      withdrawal_amount = 25.0
+      account = Bank::CheckingAccount.new(12345, start_balance)
+
+      updated_balance = mulitple_check_withdrawal(3, account, withdrawal_amount)
+
+      expected_balance = start_balance - withdrawal_amount * 3
+
+      account.balance.must_equal expected_balance
+      updated_balance.must_equal expected_balance
     end
 
     it "Applies a $2 fee after the third use" do
-      # TODO: Your test code here!
+      start_balance = 100.0
+      withdrawal_amount = 25.0
+      fee = 2.0
+      account = Bank::CheckingAccount.new(12345, start_balance)
+
+      updated_balance = mulitple_check_withdrawal(4, account, withdrawal_amount)
+
+      expected_balance = start_balance - withdrawal_amount * 4 - fee
+
+      account.balance.must_equal expected_balance
+      updated_balance.must_equal expected_balance
+    end
+  end
+
+  # Calls withdraw_using_check num times
+  # returns updated_balance
+  def mulitple_check_withdrawal(num, account, withdrawal_amount)
+    updated_balance = nil
+    num.times do
+      updated_balance = account.withdraw_using_check(withdrawal_amount)
     end
+    updated_balance
   end
 
   describe "#reset_checks" do
     it "Can be called without error" do
-      # TODO: Your test code here!
+      account = Bank::CheckingAccount.new(12345, 100.0)
+      account.reset_checks
     end
 
     it "Makes the next three checks free if less than 3 checks had been used" do
-      # TODO: Your test code here!
+      start_balance = 200.0
+      withdrawal_amount = 25.0
+      account = Bank::CheckingAccount.new(12345, start_balance)
+
+      mulitple_check_withdrawal(2, account, withdrawal_amount)
+      account.reset_checks
+      mulitple_check_withdrawal(3, account, withdrawal_amount)
+
+      expected_balance = 200.0 - withdrawal_amount * 5
+
+      account.balance.must_equal expected_balance
     end
 
     it "Makes the next three checks free if more than 3 checks had been used" do
-      # TODO: Your test code here!
+      start_balance = 200.0
+      withdrawal_amount = 25.0
+      fee = 2.0
+      account = Bank::CheckingAccount.new(12345, start_balance)
+
+      mulitple_check_withdrawal(4, account, withdrawal_amount)
+      account.reset_checks
+      mulitple_check_withdrawal(3, account, withdrawal_amount)
+
+      expected_balance = 200.0 - withdrawal_amount * 7 - fee
+
+      account.balance.must_equal expected_balance
     end
   end
 end
diff --git a/specs/savings_account_spec.rb b/specs/savings_account_spec.rb
index 3f4d1e4a..19f0df4b 100644
--- a/specs/savings_account_spec.rb
+++ b/specs/savings_account_spec.rb
@@ -1,17 +1,9 @@
 require 'minitest/autorun'
 require 'minitest/reporters'
 require 'minitest/skip_dsl'
+require_relative '../lib/savings_account'
 
-# TODO: uncomment the next line once you start wave 3 and add lib/savings_account.rb
-# require_relative '../lib/savings_account'
-
-# Because a SavingsAccount is a kind
-# of Account, and we've already tested a bunch of functionality
-# on Account, we effectively get all that testing for free!
-# Here we'll only test things that are different.
-
-# TODO: change 'xdescribe' to 'describe' to run these tests
-xdescribe "SavingsAccount" do
+describe "SavingsAccount" do
   describe "#initialize" do
     it "Is a kind of Account" do
       # Check that a SavingsAccount is in fact a kind of account
@@ -20,39 +12,94 @@
     end
 
     it "Requires an initial balance of at least $10" do
-      # TODO: Your test code here!
+      proc {
+        Bank::SavingsAccount.new(12345, 9)
+      }.must_raise ArgumentError
     end
   end
 
   describe "#withdraw" do
     it "Applies a $2 fee each time" do
-      # TODO: Your test code here!
+      start_balance = 100.0
+      withdrawal_amount = 25.00
+      fee = 2.0
+      account = Bank::SavingsAccount.new(12345, start_balance)
+
+      updated_balance = account.withdraw(withdrawal_amount)
+      expected_balance = start_balance - withdrawal_amount - fee
+
+      # Both the value returned and the balance in the account
+      # should apply the fee
+      updated_balance.must_equal expected_balance
+      account.balance.must_equal expected_balance
     end
 
     it "Outputs a warning if the balance would go below $10" do
-      # TODO: Your test code here!
+      start_balance = 100.0
+      withdrawal_amount = 91.0
+      account = Bank::SavingsAccount.new(12345, start_balance)
+
+      # Anything printed to the console output will pass the test
+      proc {
+        account.withdraw(withdrawal_amount)
+      }.must_output (/.+/)
     end
 
     it "Doesn't modify the balance if it would go below $10" do
-      # TODO: Your test code here!
+      start_balance = 100.0
+      withdrawal_amount = 91.0
+      account = Bank::SavingsAccount.new(12345, start_balance)
+
+      updated_balance = account.withdraw(withdrawal_amount = 91.0)
+
+      # Both the value returned and the balance in the account
+      # must be un-modified.
+      updated_balance.must_equal start_balance
+      account.balance.must_equal start_balance
     end
 
     it "Doesn't modify the balance if the fee would put it below $10" do
-      # TODO: Your test code here!
+      start_balance = 100.0
+      withdrawal_amount = 90.0 # + 2.0 fee
+
+      account = Bank::SavingsAccount.new(12345, start_balance)
+
+      updated_balance = account.withdraw(withdrawal_amount = 91.0)
+
+      # Both the value returned and the balance in the account
+      # must be un-modified.
+      updated_balance.must_equal start_balance
+      account.balance.must_equal start_balance
+
     end
   end
 
   describe "#add_interest" do
     it "Returns the interest calculated" do
-      # TODO: Your test code here!
+      account = Bank::SavingsAccount.new(12345, 10_000.0)
+      rate = 0.25 # percentage
+      interest = account.add_interest(rate)
+      expected_interest = 25.0
+
+      interest.must_equal expected_interest
     end
 
     it "Updates the balance with calculated interest" do
-      # TODO: Your test code here!
+      rate = 0.25 # percentage
+      account = Bank::SavingsAccount.new(12345, 10_000.0)
+      account.add_interest(rate)
+
+      expected_balance = 10_025.0
+      account.balance.must_equal expected_balance
     end
 
     it "Requires a positive rate" do
-      # TODO: Your test code here!
+      rate = -0.25
+      account = Bank::SavingsAccount.new(12345, 10_000)
+
+      proc {
+        account.add_interest(rate)
+      }.must_raise ArgumentError
     end
   end
 end