From a constructivist's perspective, discourse is a central mechanism for learning (Palinscar, 1998). For ages, educationalists have been working on making the "theory" as practical as possible and making the "practice" as theoretically interesting as possible. This effort is the guiding force to relate constructivism as theory of learning to the practice of instruction (Savery & Duffy, n. d.). Constructivism is a philosophical view on how we come to understand or know, and the instructional principles guide us in the practice of teaching and the design of learning environments. Orchestrating constructive discourse is a complex process, whether in a classroom or otherwise (Leinhardt, 1993). Over a period of time, ever since the need to introduce problem-based learning (PBL) was understood and practiced in engineering courses the world over, its positive effects have been discussed and published time and again (Cooper, 1997; Besterfield-Sacre et al, 1997; Albanese & Mitchell, 1993). While the knowledge construction is structured, but limited, in a teacher centered classroom, the same is much more complicated, but elaborate, in the student centered approach. In PBL, thus, when the teachers and students co-construct the instructional agenda in a student centered classroom, the role of the facilitator becomes very critical as he has to juggle with many simultaneous goals and has to coordinate pedagogical actions with semantic knowledge.
In India, particularly in North India, where approximately 39 engineering colleges are established with an annual intake of 16,000 students, no instance of practicing PBL is known. Thus, the only method of imparting technical education in degree courses is the traditional lecture/tutorial/practical (L/T/P) approach. Encouraged by the success of PBL in engineering courses (Maskell & Grabau, 1998; Striegel & Rover, 2002; Linge & Parsons, 2006) elsewhere in world, and considering the importance of analogue electronics as a basic subject in the curriculum of electronics and communication engineering, PBL was introduced in this course using a two threaded approach. The existing class of 132 students was split into two parts - the Control Group (CG) and the Treatment Group (TG). The selection of students for PBL was random.
As the students went through the ups and downs of PBL and team work, progressive improvement in their knowledge, technical and communication skills, and attitude was seen and tabulated by taking periodic reflections and evaluations. In the end, their performances were compared using common tests, designed to include all aspects of knowledge and skill. This paper highlights the designing of problems; cognitive and pedagogical issues while conducting the course; analyses of solutions submitted by the groups; and the difference in the performance of CG and TG.
2 COGNITIVE AND PEDAGOGICAL ISSUES
2.1 Syllabus of analogue electronics
The syllabus of Analogue Electronics (Theory) EC202 is set to cover the following topics:
1. high Frequency analysis of transistors
2. large signal amplifiers
3. multistage amplifiers
4. feedback in amplifiers
6. regulated power supplies.
The experiments are made to include following tasks in the practical component EC210 (Palinscar, 1998), which are broadly classified as:
1. to study the characteristics of all types of large signal amplifiers
2. to study the response of all types of sinusoidal oscillators
3. to study the working of a regulated power supply.
2.2 Time allotment, teaching pedagogy and evaluation strategy
The existing class of 132 students was split into two groups: the TG was taught using PBL and the CG was taught by L/T/P. Initially 25 students were randomly selected for the TG. However, after one session, four of these students left and the TG finally had 21 students. …