Naturally, it is a novelty when something moves on the screen - very different from a textbook. However, animation can be overdone. Not only does it take a considerable time to author, it is most frustrating when you are forced to wait for the animation to finish before you can proceed to the next screen. On the first occasion it may be frustrating, on subsequent occasions it is aggravating. For this reason animations have been limited to short sequences or to sequences which can be stopped by the user.
Colour has similar problems.
We have monitored student reaction to the on-line tutorials by applying questionnaires. Other major plus points are the targeted nature of the material and the use of colour, interaction and animation. On the negative side, students felt that they should be allowed to take hard copy. This was denied them since the authors felt that it was essential that students were exposed to the logical development of the topics which would not be ensured if they worked from a print-out. This was defended on the grounds of the superior quality considered essential to the presentation, and that more recent laptops and home PCs have the SVGA resolution.