This study investigated the effect of blended learning on novices' understandings of the introductory programming. A quasi-experimental design with participants of preservice computer and instructional technologies teachers, one control group (CG, N =64) and one experimental group (EG, N=61) who received the course 11 weeks. While face-to-face courses were taught face-to-face in classroom and in lab, blended courses were conducted in synchronous and asynchronous settings and also in lab sessions. The pretest, posttest and delayed tests were used to collect data. The participants in two groups were separated into three categories (poor, average and good) according to the pretest results. The results of the study showed that blended and face-to-face courses have statistically similar effects on academic achievements among the three categories. However the delayed test results showed that, face-to-face courses were more effective on permanence than blended courses. Thus, considering the main goal of the introductory programming courses as enhancing students in the second category progress into the third, the organization of blended courses had to be revisited. Nevertheless, this study supported the idea that "Crucial challenges may exist on teaching some subjects via blended learning, which include intensive cognitive processes and some new approaches are needed to enhance permanence". (Contains 11 tables and 6 figures.)