is there a way to make a forum thread like a sticky so that people fill out for instance their raiding schedule for a week and at the end of the week it clears by it self.

Not that I know of. However there is the new Raid Availability Tracker that should show up in the Logged in As section. It doesn't reset after a week but is a place that is intended to allow people to fill in their schedules for a week. Anyone can then access the tracker and see who is available on certain days of the week and what times.

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Six Demon Bag
Jack Burton: Hey, what more can a guy ask for?
Egg Shen: Oh, a six-demon bag!
Jack Burton: Terrific, a six-demon bag. Sensational. What's in it, Egg?
Egg Shen: Wind, fire, all that kind of thing!