Studying:
Khanacademy.org
Goodreads.com
Keepmeout.com
Wolframalpha.com
Quizlet.com
Plagtracker.com
Copyscape.com/
Studygs.net/
About.com/education
Scholarpedia.org/article/Main_Page
Writtenkitten.net/
Sparknotes.com
Cliffnotes.com
Textbooks: Chegg.com http://www.slugbooks.com/ http://cnx.org/ oerconsortium.org/discipline-specific/ http://bookboon.com/ http://www.e-booksdirectory.com/ http://www.fullbooks.com/ http://www.readprint.com/ http://www.bartleby.com/ http://manybooks.net/ http://open.bccampus.ca/ http://open.umn.edu/opentextbooks/ http://en.wikibooks.org/wiki/Main_Page http://www.openculture.com/free_textbooks