Math
http://www.ixl.com
http://www.multiplication.com
http://www.abcya.com
http://www.fun4thebrain.com
http://www.aplusmath.com
Reading
http://www.abcya.com
http://connected.mcgraw-hill.com
Religion
http://www.ewtn.com/ewtnkids/home.asp
Science and Social Studies
Pearson Science and Social Studies
http://www.pearsonrealize.com
Vocabulary
Vocabulary Workshop
www.vocabularyworkshop.com