Pre-Clinical Experiences: First Impression

So I've been at my old middle school for a week now, doing some observations and I've really enjoyed it. My host teacher is my eighth grade science teacher and she has been incredible to "work" with so far. The whole team of teachers in the downstairs eighth grade is just awesome. They were all so welcoming!

I was really nervous about the first week of school. How do you get kids from summer mode to school mode? How do you lay down the law without destroying any trust or making them absolutely hate you? So many little questions...