Partner reading with paragraph shrinking has been shown to be an effective classwide reading intervention in elementary school, but has yet to be studied with eighth-grade students or with content area reading such as science and social studies. The current study examined the effects of implementing the classwide intervention for 3 wk with 86 students in eighth grade that were randomly assigned to the treatment or a control group. The intervention led to significantly higher oral reading fluency ([eta-squared] = .49), and higher scores on a researcher-created maze test for science ([eta-squared] = .10) and social studies ([eta-squared] = .13). Student variables (i.e., receiving English as a second language services, special education, or a free or reduced-price lunch) did not predict student outcomes and added negligible to small amounts of variance. Therefore, the effects seemed to be positive regardless of student-level factors. Potential implications for practice and research are included.