I don't know if I've mentioned, but the high school at which I teach is an International Baccalaureate school. It's a good system, but requires way more than is 'normal' for preparation, interdisciplinary stuff, and all steps in the teaching process.
Grades 9 and 10 are the last two years of the "Middle Years Programme," or MYP. All students participate through grade 10. Then, students may choose the challenging DP "Diploma Programme" for 11th and 12th grade.
Basically, anyone who teaches 9th and 10th has a lot of extra hoops through which to jump (boy, that sentence doesn't sound right!). All my classes are 9th and/or 10th so I have been busy!
This is a great program and all the work will be very much worth the effort, but still! Busy, busy busy!