This study explores students' perspectives on the satisfaction of basic psychological needs in the classroom and the potential effects on their learning growth in a summer reading program. The summer reading program was free for students in grades 1-8 and was designed to prevent reading-level losses during the summer for students from lower-income households or minoritized races or ethnicities. Using a mixed-method design, we tracked students' reading skill growth during the 6-week reading program; we then identified three student pairs with different patterns of change in their reading skills. Through the interview analysis, we explored what learning experiences in the classroom supported the satisfaction of basic psychological needs, especially for successful learners. Based on the findings, we suggest how teachers can support students who face difficulties with reading growth. This study's findings provide insights into autonomous motivation support and positive learning growth based on the self-determination theory. [This is the online first version of an article published on "Educational Studies."]