This study investigated the effects of intrinsic motivation, perceived competence, classroom engagement and extrinsic motivation on reading development among youth. Using a nationally representative sample of students in the US, the researchers followed students longitudinally from fifth to eighth grade. Reading achievement was measured using composite tests of vocabulary, reading comprehension and sight-word identification. Hierarchical linear regression was used to examine the effect of students' perceived intrinsic motivation and competence, as well as teacher rated classroom engagement in the 5th grade, on reading achievement in the 8th grade. Important control variables were utilised such as gender, family SES, race/ethnicity and prior reading achievement. The results showed that intrinsic motivation to read, perceived competence and engagement in 5th grade significantly predict reading achievement in 8th grade. The importance students placed upon grades also predicted reading development. Implications for promoting intrinsic motivation and strong engagement in schools are discussed.