You could do either. If you already have photos you want to start scrapbooking with, begin with Digital Scrapbooking 1. If you'd like to start with editing your photos first, begin with Photo Editing 1.
One note about Photo Editing 1: The sliders in Adobe Camera Raw (Lesson 1) changed between CS5 and CS6. So make sure you watch the video labeled "For all other versions of Photoshop." Also, I would refer to the PDF for PSE10 for specifics on how the sliders work. After Lesson 1, the workflow is essentially the same (and there are notes on the PDF about how the different programs differ).
If you get confused, drop a note in the forum for that specific class.
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