diff --git a/StringsAndTings.js b/StringsAndTings.js
index 4fdca47..e2fc90f 100644
--- a/StringsAndTings.js
+++ b/StringsAndTings.js
@@ -2,28 +2,63 @@ class StringsAndTings {
     
     // @return string with identical content, and the first character capitalized
     camelCase(str){
-        return null;
+        let strSplit = str.split(" ");
+        for (let i = 0; i < strSplit.length; i++) {
+           let word = strSplit[i];
+            strSplit[i] = word[0].toUpperCase() + word.substring(1);     
+            }
+        return strSplit.join(" ");
     }
 
     //@return string with identical contents, with each word individually in reverse order
     reverseString(str){
-        return null;
+        let reversed = "";
+        for (let i = str.length - 1; i >= 0; i--) {
+            reversed += str[i];
+        }
+        return reversed;
     }
 
+    reverseWords(str){
+        let words = [];
+        words = str.match(/\S+/g);
+        let result = "";
+        for (let i = 0; i < words.length; i++) {
+            result += words[i].split("").reverse().join("") + " ";
+        }
+        return result.trim();
+    }
     // @return string with identical contents, in reverse order, with first character capitalized
     reverseThenCamelCase(str){
-        return null;
+        let reversed = "";
+        for (let i = str.length - 1; i >= 0; i--) {
+            reversed += str[i];
+        }
+        let upperCase = reversed.split(" ");
+        for (let i = 0; i < upperCase.length; i ++) {
+            let word = upperCase[i];
+            upperCase[i] = word[0].toUpperCase() + word.substring(1);
+        }
+        return upperCase.join(" ");
     }
 
     // @return string with identical contents excluding first and last character
     removeFirstAndLastCharacter(str){
-        return null;
+        let result = str.slice(1, -1);
+        return result;
     }
 
     // @return string with identical characters, each with opposite casing
     invertCasing(str){
-        return null;
+       let newWord = [];
+       for ( let i = 0; i < str.length; i++) {
+           if ( str[i] == str[i].toLowerCase()) {
+               newWord[i] = str[i].toUpperCase();
+           } else {
+               newWord[i] = str[i].toLowerCase();
+        }
+            }
+            return newWord.join("");
+        }
     }
-}
-
 module.exports = StringsAndTings;
\ No newline at end of file
diff --git a/StringsAndTings.test.js b/StringsAndTings.test.js
index 689b63d..31948d2 100644
--- a/StringsAndTings.test.js
+++ b/StringsAndTings.test.js
@@ -8,7 +8,7 @@ test("camelCaseTest", () => {
     let input = "she sells sea shells";
     let expected = "She Sells Sea Shells";
 
-    let actual = stringsAndTings.camelCase(15);
+    let actual = stringsAndTings.camelCase(input);
 
     expect(actual).toEqual(expected);
 });
@@ -19,7 +19,7 @@ test("reverseTest", () => {
     let input = "she sells sea shells";
     let expected = "sllehs aes slles ehs";
 
-    let actual = stringsAndTings.camelCase(15);
+    let actual = stringsAndTings.reverseString(input);
 
     expect(actual).toEqual(expected);
 });
@@ -30,7 +30,7 @@ test("reverseWordsTest", () => {
     let input = "she sells sea shells";
     let expected = "ehs slles aes sllehs";
 
-    let actual = stringsAndTings.camelCase(15);
+    let actual = stringsAndTings.reverseWords(input);
 
     expect(actual).toEqual(expected);
 });
@@ -41,7 +41,7 @@ test("reverseThenCamelCaseTest", () => {
     let input = "she sells sea shells";
     let expected = "Sllehs Aes Slles Ehs";
 
-    let actual = stringsAndTings.camelCase(15);
+    let actual = stringsAndTings.reverseThenCamelCase(input);
 
     expect(actual).toEqual(expected);
 });
@@ -52,7 +52,7 @@ test("removeFirstAndLastCharacterTest", () => {
     let input = "she sells sea shells";
     let expected = "he sells sea shell";
 
-    let actual = stringsAndTings.camelCase(15);
+    let actual = stringsAndTings.removeFirstAndLastCharacter(input);
 
     expect(actual).toEqual(expected);
 });
@@ -64,7 +64,7 @@ test("invertCasingTest1", () => {
     let input = "shE sells SEA sHeLlS";
     let expected = "SHe SELLS sea ShElLs";
 
-    let actual = stringsAndTings.camelCase(15);
+    let actual = stringsAndTings.invertCasing(input);
 
     expect(actual).toEqual(expected);
 });