If it's with homework, my answer is different than if they get frustrated having to clean their room or get dressed & ready for school.
Without more detail, I would try to cut the job into bite-sized pieces for them. Have them do 10 math problems, then take a 15 minute break. Then do more.
Or, on a room, I'd ask them to just pick up the dirty clothes. Take 5, then come back and pick up the stuffed animals.
Or, race them to see who can pick up more trash / socks / whatever.
I usually tell my kids one or two steps at a time for getting ready. (Go brush your hair and teeth. Go put on socks and shoes. Find your coat and backpack.) "Get ready," is too general.
Usually, if the kid is frustrated, it's because the job is more than they can handle, or more than they THINK they can handle.
at 4:51 PM on Jan. 11, 2009