<html>
<head>
<script type="text/javascript" src='http://code.jquery.com/jquery-1.5.2.js'></script>
<script type="text/javascript">
$(document).ready(function(){
$("button").click(function () {
$("p").slideToggle("slow");
});
});
</script>
</head>
<body>
<button>Toggle</button>
<p>
This is the paragraph.
</p>
</body>
</html>