Alex Sch

<div class="checkbox">
    <label><input type="checkbox" class="two"></label>
</div>
<div class="checkbox">
    <label><input type="radio" name="rad" class="two"></label>
</div>
<div class="checkbox">
    <label><input type="radio" name="rad" class="two"></label>
</div>
<div class="checkbox">
    <label><input type="radio" name="rad" class="two"></label>
</div>

$(document).delegate('.two', 'click', function(){
	$('.two').each(function(a, b){
    	if($(b).prop('checked') == true){
    		$(b).parent().addClass('checked');
    	}else{
    		$(b).parent().removeClass('checked');
        }
    });
});