The abundant notations made on all your mid-term papers are standard copy-editing symbols. Here is a helpful link that explains several in detail with example. As detailed in lecture, two idiosyncratic symbols I add are "hmm..." -- when the point noted is plausible but not argued to a certainty -- and "risible" -- when the statement noted is contentious to the point of inviting laughter.
I wish to compliment you all on the admirable quality of the papers that you submitted. I both enjoyed and benefited substantially from your analyses of the relevance of blogging as a dialectical complement in the scholarly study of fiction.