I've created a drupal module, it's info file, and a tpl.php for the block all in the same module directory. When I enable the module, I can see the block listed and assign it to a region. However when I view the page the block does not display. If I do a vardump on $content within block_view, the dump displays at the top of the page, and firebug shows that block is wrapped with the right div tags. I would think if you did a var dump on within the block_view function, it should display in the right region. This one is probably really simple, but it's got me stumped - any help much appreciated. Also if I title the block just to see if it shows up anywhere in the page - it's still nowhere to be seen even though admin shows it it in the region, and no filters are set to prevent it being viewed. I would think that if you gave the block a title -if it's on the page it would at least show a title even if everything else is blank.

module file:

function my_block_block_info() {
   $blocks['my_block'] = array(
      'info' => t('My Block')
   );
   return $blocks;
}

function instagram_thumbnails_block_view() {

if(arg(0) == 'node' && is_numeric(arg(1)))  {
    $id = arg(1);
}     
   $query = "SELECT * FROM table WHERE id= :id AND deleted=0";
   $args = array(':id' => $id);  
   $result = db_query($query,$args)->fetchAll();
   foreach($result as $item) {
     $stuff[] = array($item->stuff_url,$item->stuff_name);
   }
   $content=
      theme_render_template(drupal_get_path('module','my_module').'/'.'block--      my_block.tpl.php',array("stuff" => $stuffs));
   return $content;
   }

block--my_block_tpl.php

<div class="wrapper">
 <?php      

 foreach($stuffs as $thing) {
 for($i=0; $i < count(thing); $i++) {
       //print out result passed from module
  } 
  }
 ?>
 </div>