function showMenu(menu_submenu) {
	menu_submenu = menu_submenu.split('_')
	menu = menu_submenu[0]
	if(menu_submenu == '') menu = onzeschool
	submenu = ''
	if(menu_submenu.length == 2)	submenu = menu_submenu[1]
	if(menu_submenu.length == 3) submenu = menu_submenu[1] + '_' + menu_submenu[2]
	if(menu_submenu.length == 4) submenu = menu_submenu[1] + '_' + menu_submenu[2] + '_' + menu_submenu[3]
	
	menus = document.getElementsByClassName('button');
	for(i = 0; i < menus.length; i ++) {
		if(menus[i].parentNode.children.length > 1) {
			if(menus[i].parentNode.children[1].id == menu) {
				menus[i].parentNode.children[1].style.display = 'block';
				for(j = 0; j < menus[i].parentNode.children[1].children.length; j ++) {
					if(menus[i].parentNode.children[1].children[j].children[0].id == submenu) {
						//menus[i].parentNode.children[1].children[j].style.textDecoration = 'underline';
						menus[i].parentNode.children[1].children[j].style.fontWeight = 'bold';
					}
				}
				//$('#' + menu).show('slow')			
			}
			else {
				menus[i].parentNode.children[1].style.display = 'none';
				//$('#' + menu).hide('slow')
			}
		}
	}
}