Our main goal is helping students and teachers to learn and teach science in a heuristic and sometimes funny way (one of the authors has written a book entitled "The Fun of Physics", which was a national best-seller - Ref 3). We think that, notwithstanding the controversy in using virtual environments, some problems may acquire a new type of understanding from convenient computer simulations. One good example is our program "Kepler" on planetary motion: We prepare on the screen an initial scenario, reproducing a real or fictious situation in the heavens... and see how it develops according to the laws of Physics!

     On the other hand, we are aware that computers in science teaching are not the solution to some pedagogical problems, in particular they are not the elixir to educational success (Ref. 2). Anyway, the contribution of computational strategies to a new and more powerful science teaching (Ref. 3) can not be forgotten in curricula development and implementation (Refs. 4, 5 and 6).