If you haven't been the new teacher at a jr high before, prepare to listen
to whining about how much nicer the previous teacher was. They'll say that
regardless of its accuracy, just to test. Don't buy it!
Check out some Harry Wong videos or books; they work.
I usually start out the year, besides the rules and procedures stuff, with
some basic instruction such as an exercise or two from Drawing on the Right
Side of the Brain. Then I give an assignment that's pretty much guaranteed
to look good, to hook them in.
They'll try your patience, but when you get things cooking it's a fun age
Best of luck!