Have, am and will continue to. Grades 6, 7 and 8, hmmm. I currently have classes with Grades 5 and 6, they're older primary school children. I'd guess yours will be in the 9-12 year old bracket, that's where most of the work is at the moment. As I said before your biggest problem will be getting them to open their mouths, some of them can be incredibly shy. One good way is to bring in some simple scenes from plays (or get them to write some) and have them act them, insist on good acting, funny voices etc. They love boys trying to do a high pitched girl's voice and any scene with boyfriend/girlfriend has them in stitches.
Which city are you in? Any idea how many students per class? I have 40-60. I personally have never seen nor heard of any book for conversation classes. Sure there are some out there with lists of topics and debates but that's not hugely helpful. Come to think of it, how would you teach the art of conversation from a book? What the school and parents want of you (in my experience) is to get the kids talking. However, they want them talking to you all the time which is frankly not possible. I have *patiently* explained to my boss that there is no way I can have a one-on-one conversation with each student when there are 40 of them and only 40 minutes in a class!
It's very hard to plan anything until you know the level of your students, my recommendation is to have a couple of general ideas for down-the-line classes and concentrate on tomorrow's lessons. You do need to make a good impression, not wanting to pile on the pressure but you'll most likely have several teachers (including the headmaster) sitting at the back watching you for at least part of a lesson. However, introductions are soooo easy once you get into them you'll come out smelling of roses.
Another idea for class, a lot of my students have terrible pronunciation so I give them Tongue Twisters to practice. I explain the basic concept and give them one that looks easy as a sample ("Purple Paper People"x9), let them try it for a while and then set them one or two easy ones for homework. After a week or two they started getting really competitive as I got 5 or 6 up to the front to have a race each lesson.
Good luck and happy teaching
