The first time, go to this site & click Create Account. Copy/paste this ISBN Number: 0-618-18739-1
Then fill out the rest of the information and click Submit.
Now, close that tab. Click on the link above again & log in. Now you will see the online version of the McDougal Littell: Earth Science textbook. It's old, but if you want to look over information in a different way, it might be a good idea to play with.