Student: 1 essay --> 4 days to accomplish.
Teacher: 300 quizzes to grade, 3 to 5 lesson plans to develop and get materials for, 900 homework assignments to go over, 1test/quiz to create on material that will be or has been taught in the week, 30 to 40 hrs of lecture/office time to teach subject and answer questions --> 1 week to accomplish (And they don't actually need to give back any quizzes or tests to the students but do so because it "could" help the student out.)
To expand on my first comment. Let's say that you have an essay to write. We'll assume a conservative guess of about 20 people per class. Now, most teachers (at least in my school), have about 5 classes to teach, spanning over several Years/Grades. Now, most classes get essays at the same time (again, this may only be for my school). This means that they have to read and mark 20 in your class, and 20 in every other. This comes out to 100 essays, and this is a conservative guess! Reading and marking a single essay takes about 10 minutes. This means that they have to spend over 16 HOURS reading and marking, and this isn't counting their personal life or lesson plans or anything!
Teacher: 300 quizzes to grade, 3 to 5 lesson plans to develop and get materials for, 900 homework assignments to go over, 1test/quiz to create on material that will be or has been taught in the week, 30 to 40 hrs of lecture/office time to teach subject and answer questions --> 1 week to accomplish (And they don't actually need to give back any quizzes or tests to the students but do so because it "could" help the student out.)