diff --git a/koans/about_control_statements.rb b/koans/about_control_statements.rb
index f243ac8..71a7af0 100644
--- a/koans/about_control_statements.rb
+++ b/koans/about_control_statements.rb
@@ -59,12 +59,20 @@ class AboutControlStatements < EdgeCase::Koan
 
   def test_unless_statement
     result = :default_value
-    unless false
+    unless false    # same as saying 'if !false', which evaluates as 'if true'
       result = :false_value
     end
     assert_equal __, result
   end
 
+  def test_unless_statement_evaluate_true
+    result = :default_value
+    unless true    # same as saying 'if !true', which evaluates as 'if false'
+      result = :true_value
+    end
+    assert_equal __, result
+  end
+
   def test_unless_statement_modifier
     result = :default_value
     result = :false_value unless false
diff --git a/koans/about_methods.rb b/koans/about_methods.rb
index a4df4b8..5fd7725 100644
--- a/koans/about_methods.rb
+++ b/koans/about_methods.rb
@@ -62,6 +62,7 @@ class AboutMethods < EdgeCase::Koan
   end
 
   def test_calling_with_variable_arguments
+    assert_equal __, method_with_var_args.class
     assert_equal __, method_with_var_args
     assert_equal __, method_with_var_args(:one)
     assert_equal __, method_with_var_args(:one, :two)
diff --git a/koans/about_regular_expressions.rb b/koans/about_regular_expressions.rb
index 8344911..790bea3 100644
--- a/koans/about_regular_expressions.rb
+++ b/koans/about_regular_expressions.rb
@@ -84,6 +84,8 @@ class AboutRegularExpressions < EdgeCase::Koan
   def test_shortcut_character_classes_are_negated_with_capitals
     assert_equal __, "the number is 42"[/\D+/]
     assert_equal __, "space: \t\n"[/\S+/]
+    # ... a programmer would most likely do
+    assert_equal __, "variable_1 = 42"[/[^a-zA-Z0-9_]+/]
     assert_equal __, "variable_1 = 42"[/\W+/]
   end