VERY INTERESTING and efficient, and again, for some children (though this is a long time) I use it with children, 9-10 years and teenagers. Adults can, too, s' fun there (anti -stress) They like it a lot and really taught to pause, reflect, concentrate, playing and getting something nice. But to use in small doses to maintain suspense and interest. .,.,.,., He's everywhere in supermarkets and among friends.,.,.,., Be careful not to abuse it, except the pleasure will leave soon.,.,.,.,