diff --git a/.gitignore b/.gitignore
index 06323cc..cbbcfd7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
+*~
 bin
 classes
 lib
@@ -8,4 +9,3 @@ target
 .lein-deps-sum
 .lein-plugins
 .lein-repl-history
-
diff --git a/src/koans/01_equalities.clj b/src/koans/01_equalities.clj
index ed10b7b..8f76176 100644
--- a/src/koans/01_equalities.clj
+++ b/src/koans/01_equalities.clj
@@ -24,13 +24,13 @@
   (= __ (not (= 1 nil)))
 
   "Strings, and keywords, and symbols: oh my!"
-  (= __ (= "foo" :foo 'foo))
+  (= __ (= "hello" :hello 'hello))
 
   "Make a keyword with your keyboard"
-  (= :foo (keyword __))
+  (= :hello (keyword __))
 
   "Symbolism is all around us"
-  (= 'foo (symbol __))
+  (= 'hello (symbol __))
 
   "When things cannot be equal, they must be different"
   (not= :fill-in-the-blank __))
diff --git a/src/koans/04_sets.clj b/src/koans/04_sets.clj
index 0b5d14e..d6b4063 100644
--- a/src/koans/04_sets.clj
+++ b/src/koans/04_sets.clj
@@ -1,5 +1,6 @@
 (ns koans.04-sets
-  (:require [koan-engine.core :refer :all]))
+  (:require [koan-engine.core :refer :all]
+            [clojure.set :as set]))
 
 (meditations
   "You can create a set by converting another collection"
@@ -12,10 +13,10 @@
   (= __ (set '(1 1 2 2 3 3 4 4 5 5)))
 
   "You can ask clojure for the union of two sets"
-  (= __ (clojure.set/union #{1 2 3 4} #{2 3 5}))
+  (= __ (set/union #{1 2 3 4} #{2 3 5}))
 
   "And also the intersection"
-  (= __ (clojure.set/intersection #{1 2 3 4} #{2 3 5}))
+  (= __ (set/intersection #{1 2 3 4} #{2 3 5}))
 
   "But don't forget about the difference"
-  (= __ (clojure.set/difference #{1 2 3 4 5} #{2 3 5})))
+  (= __ (set/difference #{1 2 3 4 5} #{2 3 5})))
diff --git a/src/koans/07_conditionals.clj b/src/koans/07_conditionals.clj
index b33efc6..764cd09 100644
--- a/src/koans/07_conditionals.clj
+++ b/src/koans/07_conditionals.clj
@@ -1,14 +1,12 @@
 (ns koans.07-conditionals
   (:require [koan-engine.core :refer :all]))
 
-(defn explain-defcon-level [exercise-term]
+(defn explain-exercise-velocity [exercise-term]
   (case exercise-term
-        :fade-out          :you-and-what-army
-        :double-take       :call-me-when-its-important
-        :round-house       :o-rly
-        :fast-pace         :thats-pretty-bad
-        :cocked-pistol     :sirens
-        :say-what?))
+        :bicycling        "pretty fast"
+        :jogging          "not super fast"
+        :walking          "not fast at all"
+        "is that even exercise?"))
 
 (meditations
   "You will face many decisions"
@@ -40,10 +38,10 @@
           'doom
           'more-doom))
 
-  "In case of emergency, sound the alarms"
-  (= :sirens
-     (explain-defcon-level __))
+  "In case of emergency, go fast"
+  (= "pretty fast"
+     (explain-exercise-velocity __))
 
   "But admit it when you don't know what to do"
   (= __
-     (explain-defcon-level :yo-mama)))
+     (explain-exercise-velocity :watching-tv)))
diff --git a/src/koans/10_lazy_sequences.clj b/src/koans/10_lazy_sequences.clj
index 07c6858..ac8e6c4 100644
--- a/src/koans/10_lazy_sequences.clj
+++ b/src/koans/10_lazy_sequences.clj
@@ -24,5 +24,5 @@
      (repeat 10 __))
 
   "Iteration can be used for repetition"
-  (= (repeat 100 :foo)
-     (take 100 (iterate ___ :foo))))
+  (= (repeat 100 :hello)
+     (take 100 (iterate ___ :hello))))
diff --git a/src/koans/14_destructuring.clj b/src/koans/14_destructuring.clj
index 42e0940..de6a9ce 100644
--- a/src/koans/14_destructuring.clj
+++ b/src/koans/14_destructuring.clj
@@ -12,16 +12,16 @@
          [:foo :bar]))
 
   "Whether in function definitions"
-  (= (str "First comes love, "
-          "then comes marriage, "
-          "then comes Clojure with the baby carriage")
+  (= (str "An Oxford comma list of apples, "
+          "oranges, "
+          "and pears.")
      ((fn [[a b c]] __)
-      ["love" "marriage" "Clojure"]))
+      ["apples" "oranges" "pears"]))
 
   "Or in let expressions"
-  (= "Rich Hickey aka The Clojurer aka Go Time aka Macro Killah"
+  (= "Rich Hickey aka The Clojurer aka Go Time aka Lambda Guru"
      (let [[first-name last-name & aliases]
-           (list "Rich" "Hickey" "The Clojurer" "Go Time" "Macro Killah")]
+           (list "Rich" "Hickey" "The Clojurer" "Go Time" "Lambda Guru")]
        __))
 
   "You can regain the full argument if you like arguing"
diff --git a/src/koans/21_group_by.clj b/src/koans/21_group_by.clj
index 1e845d5..e7a0408 100644
--- a/src/koans/21_group_by.clj
+++ b/src/koans/21_group_by.clj
@@ -19,20 +19,20 @@
   "You can also group by a primary key"
   (= __
      (group-by :id [{:id 1 :name "Bob"}
-                    {:id 2 :name "Mike"}
+                    {:id 2 :name "Jennifer"}
                     {:id 1 :last-name "Smith"} ]))
 
   "But be careful when you group by non-required key"
   (= {"Bob" [{:name "Bob" :id 1}]
-      "Mike" [{:name "Mike" :id 2}]
+      "Jennifer" [{:name "Jennifer" :id 2}]
       __ [{:last-name "Smith" :id 1}]}
    (group-by :name [{:id 1 :name "Bob"}
-                    {:id 2 :name "Mike"}
+                    {:id 2 :name "Jennifer"}
                     {:id 1 :last-name "Smith"}]))
 
   "The true power of group-by comes with custom functions"
   (= __
      (group-by #(if (:bad %) :naughty-list :nice-list)
                [{:name "Jimmy" :bad true}
-                {:name "Jack" :bad false}
+                {:name "Anna" :bad false}
                 {:name "Joe" :bad true}])))