It is traditionally practiced by women in India as it stimulates healthy shiney hair. It is a very stimulating massage. It consists of several different strokes to the scalp, hair pulling and twisting, a bit of neck work and upper trap (shoulder) work and the deltoids. Also some chakra work through visualization and sound. I was introduced to it through a DVD by a blind Indian man, Mehta, he is an expert. http://www.indianchampissage.com/PDFs/The%20Express%20Article.pdf
In practical application, at the spa I was employed at, it made a great 1/2 hour treatment for people who wanted to try something different and liked the idea of a head massage.
I can't imagine a class being longer than 1 day and that would include lots of practice. You could buy his DVD and learn just as well for less money than a class. If DVD learning works for you.
Have fun!!