Webbased Visual DOM Training Tool

Hi all I made a web based visual Document Object Model (DOM) Training Tool for my students: http://test.datenkueche.com (you need Firefox !!!) Before I torture my students with this tools, I would like to have some feedback from php mailinglist. This tool should help to learn the DOM Object of PHP5 http://www.php.net/manual/de/ref.dom.php There are 3 demos that shows you the functionality of the tool. For interactive training there are some html/xml files in a drop down list. You can also load files from http sources. There are also some "special" training files. The time you need to finish an exercise will be stored in a "hi score" list. have fun, give feedback Bernhard