In this preregistered study, we examined factors influencing academic motivation among secondary school students (aged 13 – 15) on a day-to-day basis. Using cognitive effort-discounting (Cog-ED) as behavioral manifestation of motivation and self-report for internal motivational state, we utilized a daily diary method (two-week protocol, N = 39, total N = 342 diaries) to explore how these measures relate to daily experiences of need satisfaction (i.e., autonomy, competence, relatedness), social support, invested homework hours, stress and physical (versus online) school attendance both at within- and between-person levels. Employing Bayesian hierarchical modeling, we found that motivation to invest effort in learning (Cog-ED) and self-reported academic motivation were higher on days when students experienced greater competence. In addition self-reported academic motivation was higher on days when students experienced more social support from classmates and teachers, invested more effort in homework and physically attended school, but lower on days when students experienced more stress. Additionally, both motivation to invest effort in learning (Cog-ED) and self-reported academic motivation were higher for those with greater average levels of perceived autonomy and support from parents. Moreover, students who, on average, dedicated more time to homework, reported elevated stress levels, and received greater support from teachers reported higher academic motivation. Conversely, those with greater support from classmates reported lower academic motivation. These findings stress the importance of cultivating feelings of competence, supportive environments and stress reduction on a daily basis, while highlighting the importance of perceived autonomy, adult social support and physical school attendance for academic motivation. Importantly, the current study contributes by assessing motivation both behaviorally and via self-report, and fills a gap by extending trait-level motivation research to the daily-level.