jQuery toggle children of div

Answer 1

Create anchors at Menu and Menu2

    Menu
        
submenu1
        
submenu2


    Menu2
        
submenu3
        
submenu4

and script:

$(".dim > a").click( function ( e ){ 
   e.preventDefault() // prevent default action - hash doesn't appear in url
   $( this ).parent().find( "div" ).toggleClass( "hidden" );
});

When click anyone of link submenu belonging to it will will appear or disappear

Live demo: http://jsfiddle.net/ZxwpJ/