Self-determination theory (SDT) proposes various types of motivation which fall onto a continuum of self-determination. Some computational techniques allow the estimation of a global score of self-determination, with bifactor-ESEM modeling being a popular estimation method. However, this approach has shortcomings, including changing conceptual interpretation of both general and specific factors. In this study, we applied the bifactor S – 1 modeling strategy to estimate the continuum and explore its potential contribution. By estimating all specific factors except for intrinsic motivation, this model anchors the general factor in intrinsic motivation which is prototypical of self-determination. Tested with five samples of students from elementary school to university (Ntotal > 4000), the bifactor S – 1 modeling strategy was empirically supported, and its general factor yielded a stronger prediction of students’ outcomes (e.g., grades, anxiety) compared to the previously advocated bifactor-ESEM model. The bifactor S – 1 model also explains outcomes with high precision, and its conceptual concordance with SDT makes it easily interpretable.