This study investigates the relationship between the behavioral intention to use e-learning and academic achievement, using self-determination theory (SDT) and critical thinking as one of the 21st century skills. This study also examines how the behavioral intention to use e-learning, which mediates the effects of 21st century skills such as logical thinking and perceived utility, promotes academic performance. The approach is based on structural equation modeling using partial least squares (PLS-SEM). A survey question on the idea of self-determination and critical thinking in the 21st century was given to 346 students at King Saud University as the main method of collecting data. The obtained outcomes of students’ perceived usefulness, critical thinking in the 21st-century skills, and behavioral intention to utilize e-learning indicate a positive effect on their academic achievement in higher education institutes, and all of the surveyed students were completely satisfied with the effect of critical thinking in the 21st-century skills on behavioral intention to use e-learning. This study indicates that self-determination theory and critical thinking in the 21st-century skills, as well as communication skills over e-learning systems, enhance the students learning activities and enable the sharing of knowledge, information, and discussions, and, hence, we recommend that students utilize e-learning systems at educational institutions throughout Saudi Arabia for the purpose of learning and that they should be encouraged to do so through lecturers at higher level education institutions.