diff --git a/curriculum/challenges/english/10-coding-interview-prep/data-structures/create-a-stack-class.md b/curriculum/challenges/english/10-coding-interview-prep/data-structures/create-a-stack-class.md
index a26dec74f6..c4a493c439 100644
--- a/curriculum/challenges/english/10-coding-interview-prep/data-structures/create-a-stack-class.md
+++ b/curriculum/challenges/english/10-coding-interview-prep/data-structures/create-a-stack-class.md
@@ -77,8 +77,9 @@ The `peek` method should return the top element of the stack
 assert(
   (function () {
     var test = new Stack();
+    test.push('CS61');
     test.push('CS50');
-    return test.peek() === 'CS50';
+    return test.peek() === 'CS50' && test.peek() === 'CS50';
   })()
 );
 ```
@@ -89,8 +90,9 @@ The `pop` method should remove and return the top element of the stack
 assert(
   (function () {
     var test = new Stack();
+    test.push('CS61');
     test.push('CS50');
-    return test.pop() === 'CS50';
+    return test.pop() === 'CS50' && test.pop() === 'CS61';
   })()
 );
 ```
@@ -112,6 +114,7 @@ The `clear` method should remove all element from the stack
 assert(
   (function () {
     var test = new Stack();
+    test.push('CS61');
     test.push('CS50');
     test.clear();
     return test.isEmpty();