var doc = new Array();
function closeBox(boxID) {
	var ctrl = document.getElementById(boxID);
	var boxHeight = new Array();
	if(ctrl.style.visibility == 'hidden') {
		ctrl.style.visibility = 'visible';
		ctrl.innerHTML = doc[boxID];
		ctrl.style.height = '5em';
	} else {
		ctrl.style.visibility = 'hidden';
		doc[boxID] = ctrl.innerHTML;
		ctrl.innerHTML = "";
		ctrl.style.height = '0' ;
	}
}

<div class="box">
	<div id="news">
		<h1><a href="javascript:closeBox('box1');">最新情報</a></h1>
	</div>
	<div id="box1">
		<ul>
			<li>あひゃ</li>
			<li>かくして！</li>
			<li>見ちゃイヤ！</li>
		</ul>
	</div>
</div>
<div class="boxTopics">
	<h1>今日のtopics</h1>
	<p>閉じたときに、上の部分が開くのはたぶん、IEのバグのせいだよ。うわーん。</p>
</div>

h1 {
	margin: 0;
	padding: 0;
	font-size: 18px;
	margin-top: 0px;
	margin-bottom: 0px;
}
li {
	margin: 0;
	padding: 0;
	font-size: 100%;
	margin-left: 2em;
	list-style: square;
}
.boxTopics {
	margin-bottom: 50px;
}