Hi saeru,
You can go to the /templates/ja_kidscorner/html/com_content/article/default.php file find the line 50 and remove the following code:
// put heading to masthead
if ($document->countModules('masthead') || !$this->print || $tmpl !== 'component') {
$masthead = JLayoutHelper::render('joomla.content.masthead', array('params' => $this->params, 'title' => $this->escape($this->item->title), 'item' => $this->item, 'print' => $this->print, 'templateSettings' => $templateSettings, 'params' => $params, 'imageBg' => $imagesBg));
$document->setBuffer($masthead, array('type' => 'modules', 'name' => 'masthead', 'title' => ''));
}