explicate it with, is not the right choice of words. you want to say " explain it to 4 people.... To start you show the group the potato, which most often is a rock, and you tell them to pretend that the rock is hot as lava, and that it will burn their hands if it is not thrown to someone else within 10 seconds. Usas algo como una piedra tamaño naranja mas o menos , Algo que se puede tirar, pero hay que tirarla con cuidado a otro miembro del grupo.... La meta es que se ayudan entre ellos los alumnus, asi sue buena sue rte y que se diviertan harto.