I know it seems way early, but here is a percentage breakdown of what you can expect to see on the EOG.
Unifying Concept Grade 8 Science
Matter: Properties and Change 14–16%
Energy Conservation and Transfer 10–12%
Earth Systems, Structures and Processes 13–15%
Earth History 11–13%
Structure and Function of Living Organisms 19–23%
Ecosystems 9–11%
Evolution and Genetics 11–13%
Molecular Biology 8–10%
Total 100%
Here are some good sites with EOG review, we will not be using them in class, but are a great resource through the year for review.
http://www.proprofs.com/quiz-school/story.php?title=sms-8th-grade-science-eog-review
http://www.robeson.k12.nc.us/Page/48532
http://mrervinsclassscience.cmswiki.wikispaces.net/EOG+Science+Study+Guides