<div id="content">

<span>one</span>

<input type="text" />
<input type="text" />

<span>two</span>

<span>three</span>

<select>
        <option selected="selected" value=""></option>
                <option value="Monday">Monday</option>
                <option value="Tuesday">Tuesday</option>
                <option value="Wednesday">Wednesday</option>
                <option value="Thursday">Thursday</option>
                <option value="Friday">Friday</option>
                <option value="Saturday">Saturday</option>
                <option value="Sunday">Sunday</option>
</select>
</div>

<script type="text/javascript">
function restSel() {
document.getElementById("#content span").innerHTML="";
};
</script>

$("span").html("");

document.getElementById("content").getElementsByTagName("span")[0].innerHTML="";

for (i = 0; i < document.getElementById('content').getElementsByTagName('span').length; i++) {
    document.getElementById('content').getElementsByTagName('span')[i].innerHTML = '';
}