THE EFFECT OF IMPROVISATION OF INSTRUCTIONAL MATERIALS FOR BIOLOGY INSTRUCTION IN SENIOR SECONDARY SCHOOLS
Science education must seek to permit the individual to develop to the fullest his capacities for adjustment and continuous change in order that he may meet the problems of his day and solve them successfully when they arise. Biology, the study of living things is a science which has developed methods of its own. The structural complexity of the organisms themselves, the multiplicity of functions occurring simultaneously in organism's body and the inter-relationship between the organisms and their environment have led to methods of study unique to this particular science. Jean Bremner (2000) stated that the methods are characterized by the art of scientific investigation in relation to pupils' study of new specimen, the experimental approach to biological science in relation to experiment carried out by the individual study. These are necessary for the effective transfer and permanent communication of biological knowledge.
Practical experience in any science for that matter is crucial for proper understanding of any principle and application of the knowledge in that subject for cognitive growth and technological orientation and advancement. In appreciation of this fact, Lee (1999) emphasized that if biology is to perform the above role of improving the society, then the biology teacher must do the following:
Therefore activities such as collecting of materials, observing, recording observations, classifying and carrying out field work should be well encouraged. The method for achieving this is through visual instruction. It was the original method in biological science when the naturalist devoted his study to organisms as he found them in nature. The result of his work, he wrote down to be passed on to others. The knowledge was finally put in form of books. As the study of biology becomes more popular in schools, and number of students increased, it becomes more difficult to study original materials. Part of this difficulty comes by the use of laboratory, preserved materials and chart and models. But the pressure of larger number of students and increasing cost caused this situation to be abandoned most times. Miller and Blaydes (2001) asserted that the result has been that an increasing proportion of biology teaching has been done from books and lecture notes. This situation to a large extent is responsible for the poor performance in the senior secondary school certificate examinations conducted by West African Examination Council. In Nigeria, the educational system has been facing a lot of critical problems amongst which are increasing enrolment, shortage of qualified teachers, absence of laboratories and in many cases presence of laboratories but acute shortage of necessary teaching and learning materials.
The Federal Government of Nigeria through the Federal Ministry of Education with the assistance of UNESCO in 1998 established a science equipment centre to provide course for science teachers and laboratory assistants. The provision of this centre though laudable has been inadequate. Teachers of biology and other sciences therefore have to acquire and develop skills of producing teaching materials. This is what improvisation is all about. It is the process of providing quickly in time of need, using whatever happens to be available, the materials and equipment for facilitating the teaching of biology. Otitoju (2000) opined that in biology teaching nature presents a rich laboratory because specimens of plants and animals are abundant around us, however equipment needed for capturing animals. Performing physiological experiment, timing experiment or processes as well as some specimens which are available have to be improvised using locally available materials and a little imagination. The essential qualities of any improvised teaching aid are accuracy, realism, comprehensibility and interest.