Media: text, audio, video and computing This chapter and the next explore the factors affecting the costs of developing, producing and distributing open and distance learning materials.

Sparkes's estimate (see Table 10.1) that it takes 50 to 100 hours of academic staff time to develop a text that will keep a student occupied for one hour suggests that the cost ofdeveloping text is a major part of the cost ofmost distance-taught text-based courses. However, Sharratt (1993: 118) makes the valid point that the time taken to develop textual material depends on a number of factors, including the level of the subject matter, the extent to which the author is writing from experience of previous text-based or lecture-delivered courses, the author's experience of writing open learning courses and the length of the course.