In case anyone needs it, more detail on options here:
http://365.webbrewers.com/blog/Lists/Posts/Post.aspx?ID=30
"Adding javascript to a 2013 public site page isn't as straightforward as it is in most properly designed content management systems. The choices presented by the page editor are the "embed code" tool, the "edit html source" tool and buried away under web parts – the script editor web part. As far as I can tell here's how all 3 work:
The Embed Code Tool:
This is the strangest of the Microsoft script insertion concoctions – it detects if your insertion starts with a tag and adds a script editor web part if it does. If it doesn't, it simply adds a "snippet" of code to the page's source – and strips out any javascript. So if you want to add an INLINE js event like an onclick event for a pop up within a link, this option will stri ....."