Every good composition textbook will tell you that revising a paper requires more than merely editing parts of the prose to ensure they are grammatically correct.
Revision requires seeing your paper as whole with a critical eye--and usually, through the lens of others' critical eyes––and making meaningful improvements. Correcting an error will help you in the short run, but it will not ensure that you've learned anything lasting about yourself as a writer; nor will it necessarily prevent you from making the same errors again in future work.
When you receive feedback on your written work, you may find it difficult to stomach; criticism is always hard, even when it's constructive and designed to help you. (Believe me, I've been rejected from journals enough to know this feeling well.)
I'll show you an example in class of what this feedback looks like at the professional academic level
and I'm also sending you my comments on Assignment 9 3/4 so that you can get feedback that will help you revise and produce a final draft together. (The process of revising Assignment 9 3/4 together will also give you insight into writing and revising your own paper for Assignment 10.)
You'll find that my comments on your collaborative drafts are extensive and probably overwhelming as well. I give my reaction to all aspects of your work at once, in the moment as I read, and then I write a set of holistic/end-comments that come at the end of the paper. I understand that this approach can make it difficult for you to determine what to do first and how to proceed; I recommend that you start by reading the longer commentary I've written at the end of your document. Then you can go through the document, paragraph by paragraph and see how the paper elicited responses in your reader as you go.
In most cases, you will want to save grammatical errors and other aspects of the paper’s prose for last in your revision process. We'll talk through my comments and you'll decide as a group what needs to be done over at least two full days of class.
You should also be thinking about Assignment 10, of course, and how you can write as strong a paper on your own as you have drafted together.