var teach = jQuery('li#teach');
var teach_sub = jQuery('li#teach #subNav');

function showSub(e){
	jQuery(teach).addClass('Active');
	jQuery(teach_sub).css('visibility', 'visible');
}

function hideSub(e){
	if(e.currentTarget.id == 'subNav')
		return;

	jQuery(teach_sub).css('visibility', 'hidden');
	jQuery(teach).removeClass('Active');
}

jQuery(teach).hover(showSub, hideSub);
jQuery(teach_sub).hover(showSub, hideSub);