Hands are for helping, not hurting

When I was doing my student teaching in college, I heard a sweet, patient kindergarten teacher say to her students, "Hands are for helping, not for hurting." 

It was such a simple statement, easy to say and remember, and it has stayed with me throughout the years.

In our house, I've used that statement many times, but let's be honest. There are only so many times that you can say it calmly or sweetly, unless you're medicated.  And most of the time, their hands are used for hurting when the sweet cherubs are in an enclosed environment....say, the van.
What's a mom to do, when she's flying driving down the interstate going 80 70 and the four kids in the back are doing God knows what to each other????

Tell them to sit on their hands.

You heard me.  I tell those kids to sit on their hands.  Yes they whine and complain saying things like, "it hurts", but that's when I calmy say, "Hands are for helping, not for hurting, right?"
Bam.  Got 'em.