Age group(s) for which this technique is helpful:
Elementary School

Primarily used to improve behavior:
At Home

Instructions for using this technique:
My son, of course, has favorite TV shows and videos. I've used this method to "get things done!!" Example: "Johnny, it's 8 o'clock in a 1/2 hour, that's one show, you need to brush your teeth and get ready for bed," or "We need to run some errands. It'll take about an hour and a 1/2, that's the time it takes to watch a video."
If we are going to be somewhere for more time, I use the school day hours. "We'll be at Grandma's from 8:30 to 3:30, that's from the time you take the school bus till you get home." I say the hours and minutes, am & pm, so he learns by hearing how time is spoken.

I've used this technique and it works like a charm. If attention different kids have time to process info BEFORE it needs to be done, they handle tasks better.