This study evaluated the effectiveness of a comprehension program integrated with social studies instruction designed for at-risk second graders. The program included instruction in cause-effect text structure, emphasizing clue words, generic questions, graphic organizers, and the close analysis of specially constructed cause-effect target paragraphs. This program was compared (a) to a content-only program that focused only on social studies and did not include text structure instruction and (b) to a no-instruction control. Fifteen classroom teachers, randomly assigned to treatment, provided the instruction. The program improved the comprehension of instructional cause-effect texts, and there were transfer effects on some comprehension measures. The performance of the 2 instructed groups did not differ on any of the content measures, indicating that such integrated instruction can be accomplished without a loss in the amount of content acquired. This study supports our previous findings on the effectiveness of explicit instruction at the primary-grade level.