A pilot father's tough love....
Most people today think it improper to discipline children, and I have tried lots of methods to control my kids when they have had one of 'those moments.'
Since I'm a pilot, the one that I have found most effective is for me to just take the child for a flight during which I say nothing and give the child the opportunity to reflect on his or her behaviour.
I don't know whether it's the steady vibration from the engines, or just the time away from any distractions such as TV, video games, computer, iPod, etc.
Either way, my kids usually calm down and stop misbehaving after our flight together. Also I believe that eye to eye contact during these sessions is an important element in achieving the desired results.
I've included a photo below of one of my sessions with my son, in case you would like to use the technique...
Should work with the grandkids, too !