wow elphaba, that was like, waaaaaaaaay generous. Okay mamaduck deserves it, but I think I've been so lame here lately. I guess moving does that.
Anyway, I would be upset over a box of cereal dumped on the floor too. Not screaming or raving, but probably talking fast and flustered. I really get weird about big spills, I am tired just looking at it all there on the floor.
I think prevention is key. At two you can basically count on this kind of stuff. So just don't give them a bowl of anything. Get really small cups and put a few pieces in at a time. Small cups look full when they aren't. If they want a "Full bowl" put in like two more pieces and then change the subject. Feed yourself from a little bowl to be really convincing .
If I were really frustrated and my toddler dumped stuff on purpose, I might call them on it. "Oh good, I get to eat what I pick up. It's all just for me. " and just start eating while I picked it up real fast. I would totally ignore ds, and appear totally thrilled. With ds, he could not resist those kinds of motivators.
Even at 7, if he refused to run errands and I said "Oh good, I love staying home. Lets always stay home" and started reading magazines and ignoring him, he would beg to run the errands. I know he knows that I am only half serious, but it doesn't matter. The result is he stops being contrary and laughs and begs to go out. I sometimes carry on a bit longer, doing a parody of him, saying 'No thanks, I want to play Gameboy. Where did I put it? I have a few dozen games to try. Call me when it's dark out and time for bed, okay?". I tell him where the car keys are and offer him the shopping list. He goes nuts begging me to cut it out and run my errands with him. I am hopeless, aren't I?
I don't usually do this, really I don't.
But it does seem to be an innate part of human behaviour, that we get some satisfaction out of being contrary occasionally. And we stop it the minute we are taken seriously.
I totally do this sometimes to dh. I know we all do.
If I thought my toddler was genuinely experimenting, I'd ask for help picking up. But they would give it if that was their motive, so it wouldn't be an issue.
Its the "contrary on purpose just 'cause" behavior that has made me want to respond with "Oh good, Cereal on the floor. Please don't touch that, I want it all for myself thank you". Because I know ds would not be able to ignore it.
Probably it is best to be totally neutral, state your interest that they help, and pick it up yourself until they outgrow that stage.
But if you just can't stand to be saddled with a floor of cereal one more time by a hit and run cereal-dumper-who-is-watching-to-see-how-you-react, I would react like this if it helped me keep my cool (which it would).