title: Why is my block not showing?
body: <p>I don't know why my block isn't showing up. It's not showing up on any page, and I cleared the cache. Can someone help me figure out what I missed? However, the <code>var_dump('test')</code> shows up!</p>
  
  <p>app/design/frontend/default/default/template/justin/head.phtml</p>
  
  <pre><code>testing this block
  </code></pre>
  
  <p>Justin/Bieber/Block/Sings.php</p>
  
  <pre><code>class Justin_Bieber_Block_Sings extends Mage_Core_Block_Template
  {
      protected function _construct()
      {
          parent::_construct();
          var_dump("test");
      }
  }   
  </code></pre>
  
  <p>config.xml</p>
  
  <pre><code>&lt;frontend&gt;
         ...
      &lt;layout&gt;
          &lt;updates&gt;
              &lt;bieber&gt;
                  &lt;file&gt;justin.xml&lt;/file&gt;
              &lt;/bieber&gt;
          &lt;/updates&gt;
      &lt;/layout&gt;
  &lt;/frontend&gt;
  &lt;global&gt;
      &lt;blocks&gt;
          &lt;bieber&gt;
              &lt;class&gt;Justin_Bieber_Block&lt;/class&gt;
          &lt;/bieber&gt;
      &lt;/blocks&gt;
      ...
  &lt;/global&gt;
  </code></pre>
  
  <p>app/design/frontend/default/default/layout/justin.xml</p>
  
  <pre><code>&lt;?xml version="1.0"?&gt;
  &lt;layout version="0.1.0"&gt;
      &lt;default&gt;
          &lt;reference name="head"&gt;
              &lt;block type="bieber/bieber" name="justin_bieber"&gt;
                   &lt;action method="setTemplate"&gt;
                      &lt;template&gt;justin/head.phtml&lt;/template&gt;
                  &lt;/action&gt;
              &lt;/block&gt;
          &lt;/reference&gt;
      &lt;/default&gt;
  &lt;/layout&gt;
  </code></pre>