Major compatibility issue in firefox

My site works fine in IE 8/9 and Chrome, and I thought it was working fine in Firefox until I went to the tech school page http://www.alphadriver.com.au/tech-school/

and the headers/footers and sidebars show up but there is no content in the page!

This is obviously a serious issue and I’ve got no idea why yet, I’m trying to debug but it passes the html validator so I’m not sure whats wrong.

Any help is greatly apprecaited. (Or even a yay or nay if its happening with your version of firefox will help)