<p>I created this Facebook group for peer grading essays a while back, it's sort of dead now, but if enough people join/etc. it'll work:
<a href="https://www.facebook.com/groups/155041734619681/%5B/url%5D">https://www.facebook.com/groups/155041734619681/</a></p>
<p>bump. I see lots of people wanting essays graded.</p>