Teaching abstract subjects to students studying towards a degree in electronics practical engineering (a degree between a technician and an engineer) requires didactic tools that enable understanding of issues without using advanced mathematics and physics. One basic issue is the BJT (Bipolar Junction Transistor) that requires preliminary knowledge of semiconductor basics and modern physics, which is not addressed in the curriculum. Existing teaching methods reinforce students' tendency to use familiar formulas, without discussing the BJT internal structure and without comprehending the nature of the current. Therefore, it is not surprising that students do not understand the manner in which the current flows in a device that can be described as two back-to-back diodes. This article shows preliminary results of a study in which a computer animation was developed in order to depict the dynamic processes in BJT, and compares the academic achievements of students who learned BJT via animation to those who learned via static diagrams. 41 students were randomly divided into two groups, 21 students in the experimental group and 20 students in the control group. The experimental group received explanations including animation while the control group received traditional explanations using a blackboard but no animation. A comparison was made between the students' achievements in both groups via a pretest. After learning about BJT, a posttest and new comparison was conducted. The comparison referred to two categories: A. Total score on the test; B. Score on questions that require higher level of thinking. The pretest results showed no significant difference between the groups' achievement. In contrast the results of the posttest were significant, showing a 12-point advantage in the average total score, and about a 14-point advantage in the average on higher level thinking questions in the experimental group as opposed to control group. Thus, while the results of the study are preliminary, it is encouraging and important to present the results.