Return both a form and content in a menu callback
In Drupal 7 drupal_get_form() returns a render array instead of a string, so you should return a render array as well:

return array(
  'my_content' =&gt; array(
    '#type' =&gt; 'markup',
    '#markup' =&gt; 'Some markup',
  ),
  'my_form' =&gt; drupal_get_form(...),
);