diff --git a/koans/AboutApplyingWhatWeHaveLearnt.js b/koans/AboutApplyingWhatWeHaveLearnt.js
index e43eb746a..22f69db43 100644
--- a/koans/AboutApplyingWhatWeHaveLearnt.js
+++ b/koans/AboutApplyingWhatWeHaveLearnt.js
@@ -12,7 +12,7 @@ describe("About Applying What We Have Learnt", function() {
        { name: "Blue Moon", ingredients: ["blue cheese", "garlic", "walnuts"], containsNuts: true },
        { name: "Taste Of Athens", ingredients: ["spinach", "kalamata olives", "sesame seeds"], containsNuts: true }
     ];
-  });
+  });  
 
   /*********************************************************************************/
 
diff --git a/koans/AboutArrays.js b/koans/AboutArrays.js
index 6fe4313cc..14ec253eb 100644
--- a/koans/AboutArrays.js
+++ b/koans/AboutArrays.js
@@ -3,16 +3,16 @@ describe("About Arrays", function() {
   //We shall contemplate truth by testing reality, via spec expectations.  
   it("should create arrays", function() {
     var emptyArray = [];
-    expect(typeof(emptyArray)).toBe(FILL_ME_IN); //A mistake? - http:javascript.crockford.com/remedial.html
-    expect(emptyArray.length).toBe(FILL_ME_IN);
+    expect(typeof(emptyArray)).toBe('object'); //A mistake? - http:javascript.crockford.com/remedial.html
+    expect(emptyArray.length).toBe(0);
 
     var multiTypeArray = [0, 1, "two", function () { return 3; }, {value1: 4, value2: 5}, [6, 7]];
-    expect(multiTypeArray[0]).toBe(FILL_ME_IN);
-    expect(multiTypeArray[2]).toBe(FILL_ME_IN);
-    expect(multiTypeArray[3]()).toBe(FILL_ME_IN);
-    expect(multiTypeArray[4].value1).toBe(FILL_ME_IN);
-    expect(multiTypeArray[4]["value2"]).toBe(FILL_ME_IN);
-    expect(multiTypeArray[5][0]).toBe(FILL_ME_IN);
+    expect(multiTypeArray[0]).toBe(0);
+    expect(multiTypeArray[2]).toBe('two');
+    expect(multiTypeArray[3]()).toBe(3);
+    expect(multiTypeArray[4].value1).toBe(4);
+    expect(multiTypeArray[4]["value2"]).toBe(5);
+    expect(multiTypeArray[5][0]).toBe(6);
   });
 
   it("should understand array literals", function () {
@@ -23,36 +23,36 @@ describe("About Arrays", function() {
     expect(array).toEqual([1]);
     
     array[1] = 2;
-    expect(array).toEqual([1, FILL_ME_IN]);
+    expect(array).toEqual([1, 2]);
     
     array.push(3);
-    expect(array).toEqual(FILL_ME_IN);
+    expect(array).toEqual([1, 2, 3]);
   });
 
   it("should understand array length", function () {
     var fourNumberArray = [1, 2, 3, 4];
 
-    expect(fourNumberArray.length).toBe(FILL_ME_IN);
+    expect(fourNumberArray.length).toBe(4);
     fourNumberArray.push(5, 6);
-    expect(fourNumberArray.length).toBe(FILL_ME_IN);
+    expect(fourNumberArray.length).toBe(6);
 
     var tenEmptyElementArray = new Array(10); 
-    expect(tenEmptyElementArray.length).toBe(FILL_ME_IN);
+    expect(tenEmptyElementArray.length).toBe(10);
 
     tenEmptyElementArray.length = 5;
-    expect(tenEmptyElementArray.length).toBe(FILL_ME_IN);
+    expect(tenEmptyElementArray.length).toBe(5);
   });
 
   it("should slice arrays", function () {
     var array = ["peanut", "butter", "and", "jelly"];
     
-    expect(array.slice(0, 1)).toEqual(FILL_ME_IN);
-    expect(array.slice(0, 2)).toEqual(FILL_ME_IN);
-    expect(array.slice(2, 2)).toEqual(FILL_ME_IN);
-    expect(array.slice(2, 20)).toEqual(FILL_ME_IN);
-    expect(array.slice(3, 0)).toEqual(FILL_ME_IN);
-    expect(array.slice(3, 100)).toEqual(FILL_ME_IN);
-    expect(array.slice(5, 1)).toEqual(FILL_ME_IN);
+    expect(array.slice(0, 1)).toEqual(['peanut']);
+    expect(array.slice(0, 2)).toEqual(['peanut', 'butter']);
+    expect(array.slice(2, 2)).toEqual([]);
+    expect(array.slice(2, 20)).toEqual(['and', 'jelly']);
+    expect(array.slice(3, 0)).toEqual([]);
+    expect(array.slice(3, 100)).toEqual(['jelly']);
+    expect(array.slice(5, 1)).toEqual([]);
   });
 
   it("should know array references", function () {
@@ -62,36 +62,36 @@ describe("About Arrays", function() {
       refArray[1] = "changed in function";
     }
     passedByReference(array);
-    expect(array[1]).toBe(FILL_ME_IN);
+    expect(array[1]).toBe("changed in function");
 
     var assignedArray = array;
     assignedArray[5] = "changed in assignedArray";
-    expect(array[5]).toBe(FILL_ME_IN);
+    expect(array[5]).toBe("changed in assignedArray");
 
     var copyOfArray = array.slice();
     copyOfArray[3] = "changed in copyOfArray";
-    expect(array[3]).toBe(FILL_ME_IN);
+    expect(array[3]).toBe('three');
   });
 
   it("should push and pop", function () {
     var array = [1, 2];
     array.push(3);
 
-    expect(array).toEqual(FILL_ME_IN);
+    expect(array).toEqual([1, 2, 3]);
     
     var poppedValue = array.pop();
-    expect(poppedValue).toBe(FILL_ME_IN);
-    expect(array).toEqual(FILL_ME_IN);
+    expect(poppedValue).toBe(3);
+    expect(array).toEqual([1, 2]);
   });
 
   it("should know about shifting arrays", function () {
     var array = [1, 2];
 
     array.unshift(3);
-    expect(array).toEqual(FILL_ME_IN);
+    expect(array).toEqual([3, 1, 2]);
     
     var shiftedValue = array.shift();
-    expect(shiftedValue).toEqual(FILL_ME_IN);
-    expect(array).toEqual(FILL_ME_IN);
+    expect(shiftedValue).toEqual(3);
+    expect(array).toEqual([1, 2]);
   });  
 });
diff --git a/koans/AboutExpects.js b/koans/AboutExpects.js
index 52148b243..5715798a9 100644
--- a/koans/AboutExpects.js
+++ b/koans/AboutExpects.js
@@ -2,12 +2,12 @@ describe("About Expects", function() {
 
   //We shall contemplate truth by testing reality, via spec expectations.  
   it("should expect true", function() {
-    expect(false).toBeTruthy(); //This should be true
+    expect(true).toBeTruthy(); //This should be true
   });
 
   //To understand reality, we must compare our expectations against reality.
   it("should expect equality", function () { 
-	  var expectedValue = FILL_ME_IN;
+	  var expectedValue = 2;
 	  var actualValue = 1 + 1;
 	
 	  expect(actualValue === expectedValue).toBeTruthy();
@@ -15,7 +15,7 @@ describe("About Expects", function() {
 
   //Some ways of asserting equality are better than others.
   it("should assert equality a better way", function () { 
-	  var expectedValue = FILL_ME_IN;
+	  var expectedValue = 2;
 	  var actualValue = 1 + 1;
 	
   // toEqual() compares using common sense equality.
@@ -24,7 +24,7 @@ describe("About Expects", function() {
 
   //Sometimes you need to be really exact about what you "type".
   it("should assert equality with ===", function () { 
-	  var expectedValue = FILL_ME_IN;
+	  var expectedValue = '2';
 	  var actualValue = (1 + 1).toString();
 	
   // toBe() will always use === to compare.
@@ -33,6 +33,6 @@ describe("About Expects", function() {
 
   //Sometimes we will ask you to fill in the values.
   it("should have filled in values", function () {
-	  expect(1 + 1).toEqual(FILL_ME_IN);
+	  expect(1 + 1).toEqual(2);
   });
 });
diff --git a/koans/AboutFunctions.js b/koans/AboutFunctions.js
index 77b379a3a..1ce6446d2 100644
--- a/koans/AboutFunctions.js
+++ b/koans/AboutFunctions.js
@@ -6,7 +6,7 @@ describe("About Functions", function() {
       return a + b;
     }
     
-    expect(add(1, 2)).toBe(FILL_ME_IN);
+    expect(add(1, 2)).toBe(3);
   });
 
   it("should know internal variables override outer variables", function () {
@@ -21,9 +21,9 @@ describe("About Functions", function() {
       return message;
     }
     
-    expect(getMessage()).toBe(FILL_ME_IN);
-    expect(overrideMessage()).toBe(FILL_ME_IN);
-    expect(message).toBe(FILL_ME_IN);
+    expect(getMessage()).toBe('Outer');
+    expect(overrideMessage()).toBe('Inner');
+    expect(message).toBe('Outer');
   });
 
   it("should have lexical scoping", function () {
@@ -35,7 +35,7 @@ describe("About Functions", function() {
       }
       return childfunction();
     }
-    expect(parentfunction()).toBe(FILL_ME_IN);
+    expect(parentfunction()).toBe('local');
   });
 
   it("should use lexical scoping to synthesise functions", function () {
@@ -49,7 +49,7 @@ describe("About Functions", function() {
     var increaseBy3 = makeIncreaseByFunction(3);
     var increaseBy5 = makeIncreaseByFunction(5);
     
-    expect(increaseBy3(10) + increaseBy5(10)).toBe(FILL_ME_IN);
+    expect(increaseBy3(10) + increaseBy5(10)).toBe(28);
   });
 
   it("should allow extra function arguments", function () {
@@ -58,13 +58,13 @@ describe("About Functions", function() {
       return firstArg;
     }
     
-    expect(returnFirstArg("first", "second", "third")).toBe(FILL_ME_IN);
+    expect(returnFirstArg("first", "second", "third")).toBe('first');
     
     function returnSecondArg(firstArg, secondArg) {
       return secondArg;
     }
     
-    expect(returnSecondArg("only give first arg")).toBe(FILL_ME_IN);
+    expect(returnSecondArg("only give first arg")).toBe(undefined);
     
     function returnAllArgs() {
       var argsArray = [];
@@ -74,7 +74,7 @@ describe("About Functions", function() {
       return argsArray.join(",");
     }
     
-    expect(returnAllArgs("first", "second", "third")).toBe(FILL_ME_IN);
+    expect(returnAllArgs("first", "second", "third")).toBe("first,second,third");
   });
 
   it("should pass functions as values", function () {
@@ -88,21 +88,24 @@ describe("About Functions", function() {
     };
     
     var praiseSinger = { givePraise: appendRules };
-    expect(praiseSinger.givePraise("John")).toBe(FILL_ME_IN);
+    expect(praiseSinger.givePraise("John")).toBe('John rules!');
     
     praiseSinger.givePraise = appendDoubleRules;
-    expect(praiseSinger.givePraise("Mary")).toBe(FILL_ME_IN);
+    expect(praiseSinger.givePraise("Mary")).toBe('Mary totally rules!');
       
   });
 
   it("should use function body as a string", function () {
     var add = new Function("a", "b", "return a + b;");
-    expect(add(1, 2)).toBe(FILL_ME_IN);
+    expect(add(1, 2)).toBe(3);
      
     var multiply = function (a, b) {
       //An internal comment
       return a * b;
     };
-    expect(multiply.toString()).toBe(FILL_ME_IN);
+    expect(multiply.toString()).toBe(`function (a, b) {
+      //An internal comment
+      return a * b;
+    }`);
   });    
 });
diff --git a/koans/AboutObjects.js b/koans/AboutObjects.js
index 374944e80..760a7a3e2 100644
--- a/koans/AboutObjects.js
+++ b/koans/AboutObjects.js
@@ -8,12 +8,12 @@ describe("About Objects", function () {
     });
 
     it("should confirm objects are collections of properties", function () {
-      expect(meglomaniac.mastermind).toBe(FILL_ME_IN);
+      expect(meglomaniac.mastermind).toBe("Joker");
     }); 
 
     it("should confirm that properties are case sensitive", function () {
-      expect(meglomaniac.henchwoman).toBe(FILL_ME_IN);
-      expect(meglomaniac.henchWoman).toBe(FILL_ME_IN);
+      expect(meglomaniac.henchwoman).toBe('Harley');
+      expect(meglomaniac.henchWoman).toBe(undefined);
     });
   });
   
@@ -29,7 +29,7 @@ describe("About Objects", function () {
     };
    
     var battleCry = meglomaniac.battleCry(4);
-    expect(FILL_ME_IN).toMatch(battleCry);
+    expect('They are Pinky and the Brain Brain Brain Brain').toMatch(battleCry);
   });
 
   it("should confirm that when a function is attached to an object, 'this' refers to the object", function () {
@@ -44,8 +44,8 @@ describe("About Objects", function () {
       }
     };
    
-    expect(currentYear).toBe(FILL_ME_IN);
-    expect(meglomaniac.calculateAge()).toBe(FILL_ME_IN);
+    expect(currentYear).toBe(2020);
+    expect(meglomaniac.calculateAge()).toBe(50);
   });
 
   describe("'in' keyword", function () {
@@ -62,27 +62,27 @@ describe("About Objects", function () {
 
       var hasBomb = "theBomb" in meglomaniac;
      
-      expect(hasBomb).toBe(FILL_ME_IN);
+      expect(hasBomb).toBe(true);
     });
 
     it("should not have the detonator however", function () {
 
       var hasDetonator = "theDetonator" in meglomaniac;
      
-      expect(hasDetonator).toBe(FILL_ME_IN);
+      expect(hasDetonator).toBe(false);
     });    
   });
 
   it("should know that properties can be added and deleted", function () {
     var meglomaniac = { mastermind : "Agent Smith", henchman: "Agent Smith" };
 
-    expect("secretary" in meglomaniac).toBe(FILL_ME_IN);
+    expect("secretary" in meglomaniac).toBe(false);
 
     meglomaniac.secretary = "Agent Smith";
-    expect("secretary" in meglomaniac).toBe(FILL_ME_IN);
+    expect("secretary" in meglomaniac).toBe(true);
     
     delete meglomaniac.henchman;
-    expect("henchman" in meglomaniac).toBe(FILL_ME_IN);
+    expect("henchman" in meglomaniac).toBe(false);
   });
 
 
@@ -96,14 +96,14 @@ describe("About Objects", function () {
     var colouredCircle = new Circle(5);
     colouredCircle.colour = "red";
     
-    expect(simpleCircle.colour).toBe(FILL_ME_IN);
-    expect(colouredCircle.colour).toBe(FILL_ME_IN);
+    expect(simpleCircle.colour).toBe(undefined);
+    expect(colouredCircle.colour).toBe('red');
   
     Circle.prototype.describe = function () {
       return "This circle has a radius of: " + this.radius;
     };
   
-    expect(simpleCircle.describe()).toBe(FILL_ME_IN);
-    expect(colouredCircle.describe()).toBe(FILL_ME_IN);
+    expect(simpleCircle.describe()).toBe("This circle has a radius of: 10");
+    expect(colouredCircle.describe()).toBe("This circle has a radius of: 5");
   });
 });