innnerhtml is not an HTML attribute.
It iisn't a part of JavaScript either although JavaScript has something with a simiilar name - innerHTML.
Code:
<helpgrid id="changestatus_help"/>
<script type="text/javascript">
document.getElementById('changestatus_help').innerHTML = 'This will change the status of the records.';
</script>
Also if you are really using XHTML 1 or XHTML 5 as the self closing tag indicates then you can substitute type="application/javascript" for the obsolete but still needed for IE8 and earlier type="text/javascript" since IE8 and earlier don't support either the correct type for JavaScript or XHTML but all browsers that do support XHTML also support the correct type for JavaScript.