For my practicum for Youth Literature, I worked in a first grade classroom at Harris with Judy Levins. The most important thing in doing a practicum is to let the teacher know what your purpose is in the classroom. I have worked with five teachers in Eugene and I have found that every one of them really wants to know what I hope to gain from the experience and what I hope to give. If they don't have a clear understanding of what you want to do, then they will often times delegate simple tasks like correcting or copying because they are not sure what else to have you do. If you see something in the middle of the term that you would really like to do with the kids, let the teacher know.
Along with informing the teacher of you purpose, there must also be a willingness to be flexible. My supervisor could not always let children leave a lesson to read with me because they would miss something important. My purpose in the classroom was to read with kids and to help Judy in any way she needed. I found that my willingness to help in any way caused Judy to really try hard to make time for kids to read to me.
One thing I could have done a lot better was to have a better knowledge of books. I had a goal to know the reading level of each kid and their strengths and weaknesses. I reached this goal, but then I did not know what to do with this knowledge. I should have stayed inside at recess to get really familiar with the books in the classroom. This way I would have known which book to direct a student to if they were unsure what books would be too easy or too hard.