This is a brilliant - if overpriced - piece of software from the software division of Cambridge University Press. Again it could be used with most secondary age-ranges. There is a hidden facility for changing the level of difficulty, and the amount of detail in the instructions. The suite simulates Newton's three laws of motion in two stages.

First, you practice controlling an astronaut by the cursor keys, and learn what inertia really means. This is followed by a number of graded rescue and repair missions (treated as games) to test the interactive skills supposedly acquired in part one. There may be no sound, but you do get good smooth graphics, and simple and clear ideas for teaching well, tied to the underlying scientific principles. Motion In Space for the BBC B, B+ and Master does a useful, simple job appealingly and well.