in the development of web-based educational material, a significant amount of time and real cost may be devoted to the inclusion of multimedia content. the research presented describes some of the costs involved in producing a multimedia teaching resource and the evaluation of this material by a cohort of students. the material underwent significant expert review by subject matter experts and students in the formative phase. five versions of the material were developed and used as inputs to an experiment that was designed to test a number of hypotheses by using questionnaires and tests. the data from the multiple evaluations of these versions clearly identifies the value of formative review to multimedia content and, more significantly, concludes that students perceive the material to be more useful the higher the perceived quality.

keywords.
web-based instruction, multimedia, formative review

1. introduction
in the past, traditional teachers used chalk and blackboard to deliver their knowledge to learners or students. teachers are always eager to find better ways of making the teaching process easier and more interesting and, over time, began to use instruments such as overhead projectors, computers, and videos in order to enhance their teaching methods. with recent developments, more effort has been made to prepare teaching material by using today’s computer technology, providing dynamics in the appearance of the material through animation, sound and video, both as an aid to learning and, in some cases, purely to maintain interest. computer technology is considered a merging of many technologies. the concept of combining text, graphics, sound, animation and video within a computer is commonly called multimedia. multimedia technology may help to enhance the students’ understanding of the subject from a diverse range of perspectives. educational organisations, especially those involved in distance learning, are following closely the advancement of such technology. further development of computers, combined with the development of the world wide web (www or just the web), attracted interest from both the traditional educational organisations, such as schools and universities, and the non-traditional universities, such as the open university in the uk. it has been argued (bates, 1995) that the value of technology is in its capability to reach learners not well served by conventional education institutions, to match more closely the newly emerging educational needs of an information society and to improve the quality of learning. the web with its graphical interface, ease of use and hypertext ability makes it of greater educational value than other technologies. hypertext is a method that permits the storing and linking of text and other media in logical ways such that the user can freely access it when and where required. the combination of multimedia and hypertext is sometimes called hypermedia. this method made the creation of web-based material more attractive for traditional and non-traditional universities since it has the capability to provide learners with more control over the learning process.

today, there is a need to discover or redesign methods of teaching and learning that match the use of technology to the demands of learners in the twenty-first century. k?rnesfors (1994) suggested that the education of teachers must be adapted to modern technology. student teachers are therefore one of the categories that might benefit greatly from the rapidly changing developments in web authoring, multimedia and hypermedia. the teachers of tomorrow need enough knowledge about the new methods and possibilities such that they can build their own materials as well as adapt and arrange the vast wealth of freely available material into a form that is of use to the learner. in addition, they must be able to understand and adapt to the way their students use computers and these materials.

in much of the literature, it is recommended that any educational material should be evaluated before use. formative evaluation is a component of many systematic approach models for developing educational material, whether it is text-based, video-based or computer-based. the purpose of formative evaluation is the testing and reviewing of the material before delivery and use. in contrast to summative evaluation, that is conducted after the material has been finalised, formative evaluation is intended to be carried out when the material is still under development.

the process of formative evaluation involves collecting data from a variety of sources and using a variety of data gathering methods and tools to review, test, and accordingly revise the developed material for the purpose of improving its effectiveness and appeal, which is shown in figure 1. mainly, formative evaluation is conducted through four methods: expert review, one-to-one evaluation, small group evaluation and field-test evaluation. two categories of participants as data sources are used, experts and target learners.