Jscrip, Jquery PHP and God damit!

I am currently working on a feature for the wild project which I envisioned when I was drafted in to help. When a tutor wants to add, edit or embed an activity, they will need to get the correct one from an activity set. Let me put this context:

Dr. Livingstone (no not that famous guy) teaches the University of Hamburg(er). The good Doctor is building a presentation for a lecture on the African jungles, and has decided to use an existing activity from another lecture he made with the wild project. Doc L picks the Activity set in the tutor interface via a drop down list and selects the "jungle bells: stories from the green forests" activity set. The next selection drop down list is then populated with the activities from that set, in which Doc L picks "the hills of stranglethorn vale" activity.

On to my problem:

That "cannot" be done with PHP (I "" because I haven’t found an example of it been done) you can set up the query, but that’s about it. Now it can be done with Jscript and something called JQuery which is a Library for java script. I have been looking at Different examples of JQuery and I find it could be useful in a lot of different things for wild, but it something we will be looking at later versions.

I have done some searching around and found a good example of what I am trying to achieve:

http://remysharp.com/2007/01/20/auto-populating-select-boxes-using-jquery-ajax/

(Thanks Remy)

at the moment I am trying to follow the Example he has given but am struggling to get it working locally (not sure I have the correct code in the correct files Etc) but I am confident I can convert this to use a database Ids rather than the values of the select or use the Values of the select to reference the table ids.

~Keith