The authors examined 1,781 rural students' reading motivation and behavior across the transition from middle to high school. Using expectancy-value theory, they investigated how motivational variables predicted changes in reading behavior and achievement across the transition in terms of their expectancies, values, and out-of-school reading behaviors. A repeated measures analysis of variance indicated significant increases in vocabulary, intrinsic value, and out-of-school reading, whereas significant decreases were found in attainment value. Hierarchical regression analysis indicated students' subjective expectancy for success was a significant predictor of increases in both comprehension and vocabulary scores. Students' utility value interacted with intrinsic value in predicting reading comprehension scores. In terms of change in students' reading behavior, their perceptions of intrinsic value and utility value were significant predictors. Gender interacted significantly with expectancies in predicting behaviors. Findings have implications for instructional support, particularly as it relates to reading motivation across the transition from middle to high school.