Menu Block change depth I'm converting an HTML template to a Drupal theme. The HTML template has a 2-level submenu: 
ul (main) > ul (first-level) > ul (second level).

In my block--system--main-menu.tpl.php I do only have: &lt;?php print $content ?&gt;

When I check the structure of the Main menu in Drupal (list links) levels are correct. 

Now on my frontpage Drupal shows only the first level of the menu. How can I make Drupal show more levels? I'd love to do this without a (non-core) module.

Thanks in advance!
I think you just have the primary navigation enabled in your theme. To see the second level, enable the secondary navigation in your theme settings. But this will split you're navigation. A probably better solution is, to use the "Menu Block" module. This allows you to build different kind of navigations in a block.