There is growing recognition of the need to end the debate regarding reading instruction in favor of an approach that provides a solid foundation in phonics and other underlying language skills to become expert readers. We advance this agenda by providing evidence of specific effects of instruction focused primarily on the written code or on developing knowledge. In a grade 1 program evaluation study, an inclusive and comprehensive program with a greater code-based focus called Reading for All (RfA) was compared to a knowledge-focused program involving Dialogic Reading. Phonological awareness, letter word recognition, nonsense word decoding, listening comprehension, reading comprehension, written expression and vocabulary were measured at the beginning and end of the school year, and one year after in one school only. Results revealed improvements in all measures except listening comprehension and vocabulary for the RfA program at the end of the first school year. These gains were maintained for all measures one year later with the exception of an improvement in written expression. The Dialogic Reading group was associated with a specific improvement in vocabulary in schools from lower socioeconomic contexts. Higher scores were observed for RfA than Dialogic Reading groups at the end of the first year on nonsense word decoding, phonological awareness and written expression, with the differences in the latter two remaining significant one year later. The results provide evidence of the need for interventions to support both word recognition and linguistic comprehension to better reading comprehension.