It's easy - just select the desired access level, copy this link and send it via email, instant message, etc.Link: Just a link to your wiki. Post this anywhere and people can ask you for the invite key.
Photo Files for following along with the tutorial (create a folder on your desktop to download them into - name it "earth")
Lake Alma Photos (After you follow the link, right click on each of the picture file links and choose "Save Target As..." Save it to the "earth" folder on your desktop.)
Resource from ISTE
" Power of the Mashup: Combining Essential Learning with New Technology Tools" from ISTE's Learning & Leading With Technology, Vol 35, No. 1.