Consider what follows as a possible approach to managing submissions when you have an outrageous number of high-school students in your writing classes.

The bane of every teacher is having to be their editor on issues they should already have mastered. When you have 30+ students in a class, having to re-teach high school students on how to use a comma is simply an unacceptable waste of time.

For what it is worth, my suggestion is to push as much of the pick-and-shovel work of writing onto the students. There are tools out there that provide feedback, but one, in particular, has promise and a low price tag (e.g., free) — that tool is PaperRater.

This tool can provide quantitative and qualitative feedback on a paper. It will not assess content (that is, the cognitive logic of the paper) but it will help greatly with clarity and syntax.  Both of these must be mastered before a paper can be evaluated for content.

So, how does this help you with a circus tent filled with students? First, have students use PaperRater during their draft revision process. This will deal with the need for immediate feedback and insulate the teacher from some of the pedantic aspects of early draft writing. Secondly, emphasize that if students are not getting at least a “B” on the paper (as assessed by PaperRater), they should not consider turning it in. That is not a hard and fast requirement but highly recommended to avoid having to read papers that should have never been turned in. (Teachers know what I’m talking about; the infamous zero/first draft paper that is the equivalent to brain vomit)

Once students have cleaned up and refined their work using PaperRater, teachers can further leverage the tool to provide assessments on the work the instant students turn it in. To do that, teachers should use PaperRater’s electronic submissions capability to their advantage. The capability is documented at:
http://paperrater.com/page/electronic-submissions

That capability will put the onus of generating assessments of student writing on the students the instant they turn it in. I understand that students get a “receipt” when they submit the work, but it is not clear if they get a copy of the assessment or not. In either case, they still have access to PaperRater.

Teachers will still have to evaluate the papers for content; there is no better tool for that than the human brain. But, if what you are reading is syntactically and grammatically correct, evaluating the content should be less of a chore.

Still drinking from the fire-hose, but at least you can use a ladle.

A caveat for this approach is that the free version of PaperRater is limited to 6 pages. Here’s the info from PaperRater:
We allow 6 pages at roughly 300 words/page for our free service. We have a premium service at http://premium.PaperRater.com that allows up to 15 pages. If we go higher than that, Grendel can’t fully digest your submission (he gets indigestion). Of course, if your paper exceeds the limit, you are welcome to split it up into multiple submissions.