Theoretical basis for CALL instruction design
Theoretical basis for CALL instruction design
Computers have become so widespread in schools and homes and their uses have expanded so dramatically that the majority of language teachers now think about the implications. Technology can bring about changes in the teaching methodologies of foreign language beyond simply automating fill-in-the-gap exercises.  The use of the computer in and of itself does not constitute a teaching method, but rather the computer forces pedagogy to develop in new ways that exploit the computer’s benefits and that work around its limitations.  To exploit the computers’ potential, we need language teaching specialists who can promote a complementary relationship between computer technology and appropriate pedagogic programs. 
A number of pedagogical approaches have developed in the computer age, including the communicative and integrative/experimentative approaches outlined above in the History of CALL. Others include constructivism, whole language theory and sociocultural theory although they are not exclusively theories of language learning. With constructivism, students are active participants in a task in which they “construct” new knowledge based on experience in order to incorporate new ideas into their already-established schema of knowledge. Whole language theory postulates that language learning (either native or second language) moves from the whole to the part; rather than building sub-skills like grammar to lead toward higher abilities like reading comprehension, whole language insists the opposite is the way we really learn to use language. Students learn grammar and other sub-skills by making intelligent guesses bases on the input they have experienced. It also promotes that the four skills (reading, writing, listening and speaking) are interrelated.  Sociocultural theory states that learning is a process of becoming part of a desired community and learning that communities rules of behavior. 
What most of these approaches have in common is taking the central focus away from the teacher as a conveyor of knowledge to giving students learning experiences that are as realistic as possible, and where they play a central role. Also, these approaches tend to emphasize fluency over accuracy to allow students to take risks in using more student-centered activities, and to cooperate, rather than compete.  The computer provides opportunity for students to be less dependent on a teacher and have more freedom to experiment on their own with natural language in natural or semi-natural settings.
 Role changes for teachers and students
Although the integration of CALL into a foreign language program can lead to great anxiety among language teachers,  researchers consistently claim that CALL changes, sometimes radically, the role of the teacher but does not eliminate the need for a teacher altogether. Instead of handing down knowledge to students and being the center of students’ attention, teachers become guides as they construct the activities students are to do and help them as students complete the assigned tasks. In other words, instead of being directly involved in students’ construction of the language, the teacher interacts with students primarily to facilitate difficulties in using the target language (grammar, vocabulary, etc.) that arise when interacting with the computer and/or other people.  
Elimination of a strong teacher presence has been shown to lead to larger quantity and better quality of communication such as more fluidity, more use of complex sentences and more sharing of students’ personal selves.  However, teacher presence is still very important to students when doing CALL activities. Teachers should be familiar enough with the resources to be used to anticipate technical problems and limitations.  Students need the reassuring and motivating presence of a teacher in CALL environments. Not only are they needed during the initial learning curve, they are needed to conduct review sessions to reinforce what was learned. Encouraging students to participate and offering praise are deemed important by students. Most students report preferring to do work in a lab with a teacher’s or tutor’s presence rather than completely on their own. 
Students, too, need to adjust their expectations, of their participation in the class in order to use CALL effectively. Rather than passively absorbing information, learners must negotiate meaning and assimilate new information through interaction and collaboration with someone other than the teacher, be that person a classmate or someone outside of the classroom entirely. Learners must also learn to interpret new information and experiences on their own terms. However, because the use of technology redistributes teachers’ and classmates’ attentions, less-able students can become more active participants in the class because class interaction is not limited to that directed by the teacher.  Moreover more shy students can feel free in their own students’-centered environment. This will raise their self-esteem and their knowledge will be improving. If students are performing collaborative project they will do their best to perform it within set time limits.
 Use of CALL for the four skills
A number of studies have been done concerning how the use of CALL affects the development of language learners’ four skills (listening, speaking, reading and writing). Most report significant gains in reading and listening and most CALL programs are geared toward these receptive skills because of the current state of computer technology. However, most reading and listening software is based on drills.  Gains in writing skills have not been as impressive as computers cannot assess this well. 
However, using current CALL technology, even with its current limitations, for the development of speaking abilities has gained much attention. There has been some success in using CALL, in particular computer-mediated communication, to help speaking skills closely linked to “communicative competence” (ability to engage in meaningful conversation in the target language) and provide controlled interactive speaking practice outside the classroom.  Using chat has been shown to help students routinize certain often-used expressions to promote the development of automatic structure that help develop speaking skills. This is true even if the chat is purely textual. The use of videoconferencing give not only immediacy when communicating with a real person but also visual cues, such as facial expressions, making such communication more authentic. 
However, when it comes to using the computer not as a medium of communication (with other people) but as something to interact with verbally in a direct manner, the current computer technology’s limitations are at their clearest. Right now, there are two fairly successful applications of automatic speech recognition (ASR) (or speech processing technology) where the computer “understands” the spoken words of the learner. The first is pronunciation training. Learners read sentences on the screen and the computer gives feedback as to the accuracy of the utterance, usually in the form of visual sound waves.  The second is software where the learner speaks commands for the computer to do. However, speakers in these programs are limited to predetermined texts so that the computer will “understand” them.