Lol, The transition between grade 6 and 7, is nothing compared to the transition from jr. high to high school. Im on my last year of Jr. high, and go in to level 1 high school (grade 9 to some people). The teachers for me were the same, be cause my High, Jr.High, and middle school are all attached together. The teachers wont have much of a change in personality. The homework is different. You will get your first big indefinite homework. What i mean by this is an assignment they assign at the beginning of the year, and expect done by the end of the year. No due date per say. You will have other assignments with this one so, start it early if it comes. Tests are the same basically. Midterms wont happen for you (thank god lol) But finals will. You'll stress for finals, but as long as you study before and after finals you'll do ok. BTW what i mean is, after the final itself, you get the rest of the day off to study. So if you do the final for four hours, or two hours, or one, then you get the rest of the time in the school day to study in school, or at home.
Changing classes... Hm... your teachers may still come to you, but in modules ( choice classes) you have to leave and go to another part of the school. For example, in Home Economics, you would go to the kitchen or a class room, to learn about cooking and babysitting and stuff like that, and to do cooking and stuff like that. As you can see, there is not much of a transition, but if you ever need help, guidance, advice, or other wise, feel free to PM me.