Edit in JSFiddle

Result
JavaScript
HTML

$(document).ready(function () {
        $("#after").click(function () {
            var header = $('h3').detach();
            $('#targetP').after(header);
        });
    });

<html>
<head>
<title>after</title>
</head>
<body>
<h3>This is h3 element.</h3>
<p id="targetP">This is 20Finges2Brains. This is our target.</p>
<br />
<input type="button" id="after" value="Click ME !"/>
<input type="button" value="Back To Normal" onclick="location.reload()" />
</body>
</html>