Find an intermediate to advanced tutorial from any of the following links or another tutorial site or pod cast and that you can use to give a 15 to 30 minute teaching demonstration to the class. If you find another site or particular pod cast that you recommend, please provide the link to the rest of the class.

Absolute Cross - a rich selection of high quality tutorials, resources, and imagery to help you on your way as a web developer.

Adobe Photoshop Features - Here's detailed information about the features and capabilities of Adobe® Photoshop® CS4, direct from Adobe.

Photoshop CS4 Learning Center - Tutorial videos from the National Association of Photoshop Professionals (NAPP).

Eyes on Design! If you're interested in graphics and design, and you want to learn some neat Photoshop techniques, you have come to the right place :)

Have a look at the various tips and tutorials at AdobeTV and at the Adobe Design Center.

MyJanee.com - Photoshop Resources and Tutorials.

Download a PDF sample chapter from Photoshop CS4 for Nature Photographers: A Workshop in a Book by Ellen Anon or a one from Tim Grey's Photoshop CS4 Workflow: The Digital Photographer's Guide.

Photoshop Cafe - Photoshop tutorials and resources.

Digital Retouch - the supplemental website for the book Photoshop Restoration and Retouching by Katrin Eismann (does not cover CS3 or CS4).

Another option would be to head over to Digg.com and search for "photoshop CS4 tutorial." I suggest sticking with the links with the most Diggs. Another resort would be to do an internet search for the same phrase - but good luck sifting through the immense number of options you will be provided with.