The purpose of this study was to examine the effects of prior computer knowledge and gender on high school novices' learning of computer science concepts from instructional simulations designed based an experiential-based pedagogical perspective. There were 94 10th-graders taking the introductory course on computer science identified as the low and high prior computer knowledge in this study. Participants' motivation and perceived-usefulness toward the employed instructional simulations and performance were evaluated. A quasi-experimental study was employed to examine the effects of prior computer knowledge and gender on dependent measures. The results indicated that (a) the high-prior-knowledge learners possessed higher motivation and perceived-usefulness toward the employed instructional simulations, (b) males revealed higher motivation and perceived-usefulness than females, (c) females outperformed males on the performance evaluation, and finally, (d) the low prior computer knowledge learners performed as well as the high-prior-knowledge learners while learning from instructional simulations.