My middle child is like this -- he has strong emotions and is very strong-willed besides. I've found the only way to deal with it is pull the "I'm in charge here, not you!" card. It's like it's comforting to them and helps them control their emotions when you consistently let them know what's appropriate and what's not. For example, when they start to freak out because everyone needs to start cleaning up, just tell him straight up "Throwing a fit is NOT acceptable. If you don't calm down and start cleaning up the trucks (or whatever), you will sit on the step (or whatever) until you ARE ready to." And make sure you're standing up with your arms crossed and feet wide apart (ie. assume the alpha male stance
).
I've found that teachers, babysitters, Sunday School teachers, etc., have given in to my son when he flips, and it's not helpful AT ALL. It may calm down the situation then and there, but he'll pull it again with that person soon enough.
He'll test you on it again and again, so make sure you're ready for a battle
. But when he figures out that you're not afraid to call him on his behaviour, the freak fits will lessen.