Some examples and proof of concept for using jQuery for enhancing Moodle usability.
You can try those code snippets without changing your Moodle installation by using the Firebug extension FireQuery.
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jQuery('.section h3').wrapInner('<a href="#" />')
.click( function(event) {
event.preventDefault();
jQuery(this).parent().find('ul.section').toggle();
})
jQuery('ul.section').hide();