In HTML the heading numbers h1,h2,h3,h4,h5,h6 indicate level of importance of a heading within a page sections.  Headings that are the same (in the same section) should have the same importance. You used them more to group headings down the page, Track 1 is all h2, track 2 is all h3 etc. If you copy your HTML and then go to this page and paste it in: http://gsnedders.html5.org/outliner/ you will see that there is not much of a hierarchy.

Instead, use the number to group by importance. If you use an element to make a new section like ````<article>```` or ````<section>```` then you can reuse things like h1 because they are in a different part of the page now.
````
<h1>Sessions Page</h1>

<section class="track">
    <h1>Media Arts</h1>
    <div class="session">
        <h2>Session I</h2>
        <h3>Title of Session</h3>
        <p>Description of Session</p>
        <p class="presenter">Name of Presenter</p>
    </div>

    <div class="session">
        <h2>Session 2</h2>
        <h3>Title of Session</h3>
        <p>Description of Session</p>
        <p class="presenter">Name of Presenter</p>
    </div>
    
<!-- and so on for the other sessions -->
</section>
````