$('li').click(function(e){
    	e.stopPropagation();
    	if(this.getElementsByTagName("ul")[0].style.display =="block")
    		$(this).find("ul").slideUp();
    	else
    		$(this).children(":first").slideDown();
    });

//apply this CSS (consider targeting to page/template)
 ul>li>ul {
    	display: none;
    }

//if necessary, wrap in this:
jQuery(document).ready(function($){
  
});