You need to install the TWAIN plugin to scan into Elements. Assuming this is not the App Store version, you would go to Applications>Adobe Photoshop Elements 11>Support Files>Optional Plugins and move the ImportModules folder to Applications>Adobe Photoshop Elements 11>Support Files>Plugins.
Hi Barbara B.!
Thank you so much for your prompt, clear and concise instructions. The help desks at both Adobe & Apple were not able to help me as you did. I am very grateful for your help. I hope you & your family have a great Easter.