The authors conducted an experimental study to examine the effects of collaborative strategic reading and metacognitive strategic learning on the reading comprehension of students in seventh- and eighth-grade English/language arts classes in two sites (Texas, Colorado) and in three school districts. Students were randomly assigned to classes and then classes were randomly assigned to treatment or business-as-usual comparison groups. If a teacher had an uneven number of classes, we assigned extra classes to treatment. The total number of classes randomized was 61, with 34 treatment and 27 comparison. Treatment students received a multicomponent reading comprehension instruction (collaborative strategic reading) from their English/language arts/reading teachers that included teaching students to apply comprehension strategies in collaborative groups for 18 weeks, with approximately two sessions per week. Findings indicated significant differences in favor of the treatment students on the Gates-MacGinitie Reading Comprehension Test but not on reading fluency. (Contains 8 tables and 1 note.)