Low-achieving readers in Grade 5 often lack comprehension strategies, domain knowledge, word recognition skills, fluency, and motivation to read. Students with such multiple reading needs seem likely to benefit from instruction that supports each of these reading processes. The authors tested this expectation experimentally by comparing the effects of "Concept-Oriented Reading Instruction" (CORI) with traditional instruction (TI) on several outcomes in a 12-week intervention for low achievers and high achievers. Low achievers in the CORI group were afforded explicit instruction, leveled texts, and motivation support. Compared with TI students, CORI students scored higher on posttest measures of word recognition speed, reading comprehension on the "Gates-MacGinitie Reading Test," and ecological knowledge. CORI was equally effective for lower achievers and higher achievers. Explicitly supporting multiple aspects of reading simultaneously appeared to benefit diverse learners on a range of reading outcomes. (Contains 6 tables.)