This is a very strange place to come to learn about "historical objectivity". But, I very much doubt that such a thing exists anyway.
As a former teacher I agree heartily with Acquiunk. Learning is the point of a writing assignment. This is, as you say, very much a part of the learning process.
As you read feel free to bounce ideas off of us here.
My sense is that whether it is possible to be objective is a big question and a good thing to discuss in your paper.