“…In a series of experiments designed to test the components of tutoring that lead to learning on the part of the tutor (Greer et al, 2004), Greer et al experimentally tested for the presence or absence of operants for the tutors prior to the tutors engaging in peer tutoring. In these studies, the tutors used learn-unit presentations (Albers & Greer, 1991;Bahadourian, Tam, Greer, & Rosseau, 2006;Emurian, 2004;Emurian, Hu, Wang, & Durham, 2000;Greer, 1994aGreer, ,1994bGreer, , 2002Greer & McDonough, 1999;Ingham & Greer, 1992) to tutor peers. Learn units are instructional presentations that include components of instruction that are deemed necessary, if not sufficient, conditions for learning (Greer, 1994a).…”