“…Indeed, a student may observe a phenomenon in one of the spreadsheets and wrongly conclude that it holds true in all cases, whereas in fact it may only apply to the special case being considered. As Reinhardt and Loftsgaarden (1979) point out, this is a particular problem with random simulations which, by their very nature, do not always show in a short run the results expected in the long run. Interaction with the package is therefore not only insufficient but potentially dangerous -some interaction with the teacher (whether virtual or real) is essential.…”