40 Gen Ed teachers (in grades 2, 3, and 4 classrooms were assigned in either PMI group or non PMI) (Fuchs, 1997, p. 226).

Random Stratification in Grade levels on PMI group: 4, 12, 4 Respectively (Fuchs, 1997, p. 226).

PMI group now divided into two groups: PMI and PMI Elaborate

40 classrooms; grade levels 2, 3, 4 stratified -> groups: pmi; pmi-elaborate; and no pmi or contrastEach classroom is represented by 1 LD, 1 LA, 1 AA, and 1 HA