In this contribution we report a study that aimed at the development of a powerful Logo environment for the acquisition and transfer of four thinking skills. The investigation was carried out in three sixth-grade classes according to the pretest-posttest design with control group. A 60-hour Logo course, involving the explicit training of a systematic programming strategy, was taught in two experimental classes (E1 and E2). In E2 additional explicit instruction for transfer was given. The results show that the Logo knowledge and programming skills were mastered fairly well, and that positive transfer effects were obtained for three out of the four thinking skills. Starting from our own findings on the one hand, and the results of other recent successful investigations concerning the cognitive effects of learning to program on the other, some crucial characteristics of powerful learning environments are identified and suggestions for future research are formulated.