I would like to add a simple area calculator form (length x width x depth = area) to a sidebar block, and I'm having problems figuring how to get the form to show up in the block using hook_block(). I've gotten the block to show up in the blocks list and have enabled it, but I can't get it to show up. I've been using the blocks chapter in the PDD book as a guideline, but I must be missing something. Here's what I have so far. <?php function calculate_square_form() { $form['length'] = array( '#title' => t('Length'), '#type' => 'textfield', ); $form['width'] = array( '#title' => t('Width'), '#type' => 'textfield', ); $form['depth'] = array( '#title' => t('Depth'), '#type' => 'textfield', ); $form['length'] = array( '#type' => 'button', '#value' => t('Calculate area') ); } function shbark_calculate_block($op = 'list', $delta = 0, $edit = array()) { switch ($op) { case 'list': $blocks[0]['info'] = t('Square area calculator'); return $blocks; case 'view': $block['subject'] = t('Area calcultor'); drupal_get_form('calculate_square_form'); break; } } How do I get my block content to be displayed? Do I have to pass the form to a theme function? Do I assign the form data to $block['content'] somehow? Or do I have to put the form array in the 'view' case for $op instead of a separate form function? Thanks. Steve