Grading

So our EDUC 107 professor wants us to grade our own papers???/ UGHHH I keep wondering what type of grade to give myself without being too critical as if we grade to high we have to "talk" as he says as well as if we grade to low we again have to "talk".  Keep wondering how many students will give themselves an A and how many of us are willing to be truthful and give ourselves the grade we truly deserve. What are other peoples thoughts on this new grading critique?