This study examined and quantified the maintenance of reading comprehension effects from a 4th-grade intervention for students with reading difficulties across the summer into the fall of 5th grade. We randomly assigned 4th-grade students with reading comprehension difficulties to a multicomponent reading intervention (Passport) or to typical school services. Students in the treatment received daily intervention in small groups of 4-7 students across the 4th-grade school year. We followed students (n = 269) into their 5th-grade year. Groups were equivalent at baseline, and the treatment group significantly outperformed the comparison group at posttest. Students in the treatment continued to grow in reading comprehension over the summer at a rate of approximately 25% of the original growth, which suggests partially fleeting effects of the intervention. Treatment students maintained the higher levels of reading comprehension from the end of the 4th-grade intervention to the beginning of 5th grade.