The teacher surveys
Thick fallen snow with bloodstaine--
Thousand test papers.

^^^^

I think what you have here would be considered a senryu...syllable count 5/7/5 and it's about life so..I's suggest you add (senryu) to your title? Also...when you write in this style I wouldn't capitalize each line.

The content of this is simple yet...quite brilliant because it can be taken two ways...and that's what I liked about it...

thick fallen snow with *bloodstains...(you need to correct this) indicates two things...a blank piece of paper which the student has sweated blood over getting it in on time or...red X's all over it because the teacher thinks it's all wrong....could be red ticks I guess but..don't think so?

The last line I loved...you are tired of having to correct so many papers but...it's your job.

I really...really liked this one..well done...so much said...