title: add / remove class on span inside a tag
body: <p>I've tried various options but can't get the silly thing to work. How do I get the span inside an &lt; a > tag within an &lt; li > to change class to "active"; then remove it when another &lt; a > is clicked?</p>
  
  <pre><code>&lt;ul id="dumb"&gt;
  &lt;li&gt;&lt;a href="#"&gt;Something&lt;span&gt;&lt;/span&gt;&lt;/a&gt;&lt;/li&gt;
  &lt;li&gt;&lt;a href="#"&gt;Something Else&lt;span&gt;&lt;/span&gt;&lt;/a&gt;&lt;/li&gt;
  &lt;/ul&gt;
  </code></pre>
  
  <p>Clicking the &lt; a > should give the span a class of "active" and when another is clicked, it should remove it from the original and add it to the span of that &lt; a >...</p>
  
  <p>Thanks!</p>