Sometimes when the kids are making my teaching job very difficult by not cooperating, I tell them this:
"Teaching is my JOB! Right now I am not liking my job very much. If my job was to go up and down the streets collecting the garbage cans and putting them in my truck, then it's like all of the cans are spilled. It's like all of the cans have ants on them. It's like all of the garbage cans are on fire! That's how much I am enjoying my job at this moment!"
Sometimes this calms them down and gets them to think about cooperating with me. Sometimes I have to just keep collecting the flaming garbage.