Change all four instances of:
type="application/javascript"
as in:
<script src="js/jquery-1.4.3.min.js" type="application/javascript"></script>
to:
type="text/javascript"
That fixed the menu and got the slider going - sort of. Once it was fixed it became apparent that the nivo slider section has an orphan closing </a> tag in it that should be removed (it causes a non-fatal error that makes it skip or delay at times):
<img src="images/slider_images/grads.png" alt="" title="You can save time, money, and effort!" /></a>
In case you need the larger context, that line is found (highlighted) in this section:
<!--Image Slider-->
<div class="center">
<div id="slider-wrapper">
<div id="slider" class="nivoSlider">
<img src="images/slider_images/grads.png" alt="" title="You can save time, money, and effort!" /></a>
<img src="images/slider_images/LLA.png" alt="" title="The 2011 Legislative Leadership Academy" />
<img src="images/slider_images/tech_prep_fair.png" alt="" title="Tech Prep Fair Champions" />
<img src="images/slider_images/gsrj.png" alt="" title=" Grand Slam Reading Jam Autograph Session" />
<img src="images/slider_images/fun.png" alt="" title="Even teacher training can be FUN! (Next CTE Star, 2010)" />
<!--<img src="images/nivo/Untitled4.jpg" alt="" title="#htmlcaption" /> -->
</div>
<!--<div id="htmlcaption" class="nivo-html-caption">
<strong>This</strong> is an example of a <em>HTML</em> caption with <a href="#">a link</a>.
</div>-->
</div>
<script type="text/javascript">
$(window).load(function() {
$('#slider').nivoSlider();
});
</script>
</div>