diff --git a/10_temperature_object/index.html b/10_temperature_object/index.html
index a86e7b851..3c17ebf30 100644
--- a/10_temperature_object/index.html
+++ b/10_temperature_object/index.html
@@ -49,7 +49,7 @@ <h1>Hints</h1>
 
 <p>Remember to define the <code>from_celsius</code> factory method as a <em>class</em> method, not an <em>instance</em> method.</p>
 
-<p>The temperature object's constructor should accept an <em>options hash</em> which contains either a <code>:celcius</code> entry or a <code>:fahrenheit</code> entry.</p>
+<p>The temperature object's constructor should accept an <em>options hash</em> which contains either a <code>:celsius</code> entry or a <code>:fahrenheit</code> entry.</p>
 </div>
   <div class="tests">
     <h1>Tests</h1>