•We conducted a longitudinal study with a population of high school students.•We examined potential predictors of academic motivation and high school dropout.•Teacher support for basic needs predicted only academic motivation.•Parent support for basic needs and reciprocal friendships predicted both outcomes. The purpose of this study was to examine whether parent and teacher support for basic psychological needs (i.e., autonomy, competence and relatedness), students' reciprocal friendships, and academic motivation assessed in Grade 10 (N = 624) could predict dropping out of high school two years later in Grade 12. Results revealed that reciprocal friendships contributed to the prediction of dropping out of high school, above and beyond the effects of academic motivation, or parent and teacher support for basic psychological needs. Although parent support for basic psychological needs appeared to be the most significant predictor of academic motivation and dropping out of high school, results suggested that reciprocal friendships represented an important factor that affect both motivation and persistence. Most specifically, our findings demonstrated that a lack of reciprocal friendships had detrimental effects on these aforementioned processes, whereas having reciprocal friendships lead to favorable outcomes.