Edit in JSFiddle

var news = 2;
hidenews = "- 表示を隠す";
shownews = "+ 残りを表示する";

$(".archive").html( shownews );
$(".news:not(:lt("+news+"))").hide();

$(".archive").click(function (e) {
   e.preventDefault();
       if ($(".news:eq("+news+")").is(":hidden")) {
           $(".news:hidden").show();
           $(".archive").html( hidenews );
       } else {
           $(".news:not(:lt("+news+"))").hide();
           $(".archive").html( shownews );
       }
});
div{width:200px; height:50px; margin-bottom: 15px ;background: #91d2d0 ;}
<div class="news">div 1</div>
<div class="news">div 2</div>
<div class="news">div 3</div>
<div class="news">div 4</div>
<div class="news">div 5</div>
<div class="news">div 6</div>
<a class="archive" href="#"></a>