Monday, 29 August 2011

METHODS OF TEACHING PHYSICAL SCIENCE

GENERAL METHODS OF TEACHING PHYSICAL SCIENCE
The word method originates from a Latin word which means mode or way. In the teaching of science, method refers to the way of delivering knowledge and transmitting scientific skills by a teacher to his pupils and their comprehension and application by them in the process of studying and learning science. Teaching-learning is a complex process involving teachers, students, instructional and illustrative material and the congenial atmosphere with in the class room. Knowledge of different methods of teaching helps a teacher to manipulate these factors suitably so that there is maximum benefit for the pupils. Hence it is essential that every teacher should have knowledge of different methods of teaching.
Though there are a number of methods of teaching, the teacher is free to use them according to his own abilities, interests and experiences and also of the pupils working under particular circumstances. The common methods of teaching science are described here.
A.    PROBLEM SOLVING METHOD
                Problem solving method may be defined as a planned attack upon a difficulty for the purpose of finding a solution. This involves reflective thinking for the purpose of arriving at a rational solution.
Learning of science is not merely acquisition of scientific facts. By learning science pupils are expected to have mastery of the product and process of science. When the pupils are confronted with problems of life they should be able to solve them properly. This ability is an outcome of learning science. If science is taught by using this method pupil will develop these traits.
             Phases in problem solving
In the class room situation, problem solving can be viewed in two phases
1. A way of thinking
2. A way of teaching
Stages in problem solving
1. Problem survey:-Analyzing a problem situation for details to be studied.
2. Problem description:-Providing a clear statement of the problem to be studied.
3. Problem discussion:-Making sure that the students understand what is involved in the               problem.
4. Problem limitation:-isolating those parts of the problem that can be attacked profitably.
5. Planning for action:-Preparing suitable hypothesis for investigation.
6. Further analysis and limitation:-Tentative testing of hypothesis to identify those most likely to yield a solution.
Merits
1. Children get training in the art of problem solving in actual life situations. This method inculcates the problem solving attitude
2. It helps thinking and reasoning power of the pupils.
3. It develops the power of the critical judgment as pupils have to think a lot, for arriving at correct solution through practice.
4. It is also helpful in making the students resourceful and self reliant.
5. Pupils have efficient opportunities to express themselves while discussions are going on.
6. Pupils get training in co operation and fellow feeding.
7. It inculcates the habit of open-mindedness and tolerance.
8. Learning by doing and learning by observing the concrete situations make the teaching-learning process more meaningful.
9. The teacher taught relations are strengthened. Teacher is a friend, philosopher and guide.    
10. The pupil gets valuable social experiences.
Demerits
1. It is difficult on the part of the teacher to organize the content of science according to needs of the pupils.
2. It is a time consuming method.
3. This method is not proper for immature pupils because they cannot follow and relevant material of science properly.
4. Textbooks and written materials on these lines are not easily available.
5. There is dearth of trained and competent teachers who can put this method in to practice.
B.  HEURISTIC METHOD
The name of this method is derived from the Greek word ‘Heurisco’ which means ‘I discover or I find’. Henry Edward Armstrong, Professor of Chemistry at the Imperial College, London was the advocate of this method. According to him, the real spirit of heuristic method is placing the student in the position of original investigator which means involving his ‘finding out instead of being merely told about things’. Laboratory work is essential for every pupil. A sheet instruction concerning the problem is given to every pupil and he is expected to take observations or conduct experiments in accordance with the instructions. He records his observations in his notebook. From these observations he has to draw his own conclusions or inferences. Thus he is introduced to reasoning from his own observations or experiments.

Principles underlying Heuristic method
1. The principle of activity
2. The principle of logical thinking
3. The principle of proceeding from the known to the unknown.
4. The principle of purposeful experience
5. The principle of self thinking and self study
Merits of the method
1. The maxim learning by doing is involved.
2. Power of observation and reasoning and drawing inference are developed.
3. The student becomes research becomes research minded.
4. Problem of home-task is solved.
5. The student develops himself the power of critical examination.
6. This method gives training in scientific method.
7. The knowledge is gained by self activity and hence I =t retained for a longer time.
Demerits
1. It is a very long and slow process and a hence a prescribed course cannot be covered within a specific period.
2. The experts who have to provide instructions for each topic are not available.
3. The students are immature and it is difficult for them to draw conclusions.
4. It is very costly and hence impossible for such countries as are not economically strong because well equipped laboratories are required for the purpose.
5. As no textbook is written on heuristic lines, the teacher has to work hard to arrange problems for learners.
C.  LECTURE METHOD
This is a method which is generally followed in colleges and in school with big classes. The name itself explains the procedure. The teacher talks while the pupils listen. In our class room teaching, lecture method dominates to a great extent.
In this method, the teacher acts like a chatter box, talking and talking all the time without ascertaining whether the students following him or not. The students are spoon-fed and their power of observation and reasoning, the exercise of which is so essential in the learning process are not stimulated. Thus the teacher is the only active participant in the teaching-learning process and pupils are passive listeners.
Merits
1. The method is economic. A single teacher can teach a large number of pupils using this method.
2. The method helps the teacher to cover a lengthy syllabus within a short period of time.
3. The method is concise and the teacher always feels secure and satisfied with his progress.
4. The method is useful for imparting factual information about historical incidents to the pupils.
Demerits
1. The method is against the principle of learning by doing and does not encourage the habit on independent thinking.
2. It does not provide training in scientific method and does not help the inculcation of scientific attitudes in pupils.
3. There is no assurance for the teacher whether the students have understood what he had taught in the class.
4. The rate of imparting knowledge and information may be too rapid and the students may not get necessary connections of thought.
5. It lays too much stress on memory work which is just to burden the minds of the pupils which is against the principles of teaching science.
                Lecture method is applicable in the following circumstances.
1. To introduce some new and difficult topic.
2. To revise the topics already covered.
3. To give some background of a certain topic.
4. To introduce to the life histories of great scientists and their struggles and achievements in life
5. To explain the demonstration which has been done or which is to be done.
D.  DEMONSTRATION METHOD
The teacher performs experiment relating to the topic to be taught with the active participation of the pupils. The pupils become active participants in the learning process. They feel happy and try to learn more and more as they make use of their powers of observation, reasoning and drawing inferences are properly exercised. The method, if it is accompanied by lecture that is ‘lecture-demonstrated method’ where every step of demonstration will explained by the teacher will be much more effective. The teacher should be well prepared otherwise the demonstration will be a failure which would create a very bad impression about teacher in the pupils.
This method s based on the principle “Truth is that which works”, the teacher has to work out something and then and only then student will believe.  This method is in accordance with a maxim of teaching “from concrete to abstract”.
Merits
1. It is economical as the teacher alone performs the experiment.
2. Pupils see actual things and this helps to retain what they have seen in their memory.
3. Experiments involving special type of skills and those which are dangerous can be safely Shawn in the class.
4. This method is helpful where quick revision is required.
5. The method is psychological because the students are shown concrete and confirmed facts verified practically.
6. The method helps to develop scientific attitude among pupils.
Demerits
1. There is no scope for ‘learning by doing ’which is one of the important principles of learning.
2. There is no scope of developing the practical skills of pupils as the teacher alone performs the experiments.
E.  LABORATORY METHOD
This method provides opportunities for each student to conduct experiment at his own desk in the science laboratory. The responsibility for performing experiments is shifted from the teacher to the pupils. Every pupil is provided with the laboratory manual containing instructions and the teacher merely guides and supervises pupils work. The laboratory thus, becomes a place where the teacher solves their problems.
The teacher divides the experiments in to two groups reserves one group to be performed by himself at the demonstration table and the other to be conducted by the pupils in the laboratory. In the case of delicate and costly apparatus the teacher himself can perform the experiment which the observe and make their conclusions.
Merits
1. It is a child assertive method.
2. It gives more opportunities for pupils to participate actively.
3. It gives facilities for developing the laboratory techniques and manipulative skills.

Demerits
1. It is a very expensive method.
2. a lot of time is wasted in conducting experiments.
3. The dull pupils are tempted to copy down the results of the brilliant one.
4. The teacher’s time and energy are also wasted in checking up the apparatus after every period.         
F.  PROJECT METHOD
This method is based on the philosophy of ‘Pragmatism’ founded by John Dewey. In other words we can say that the project method is an outcome of Dewey’s philosophy. As a method of teaching it was perfected by Dr.J.A Stevenson emphasis is to practical, experimental, instrumental and utilitarian basis. A project has been variously defined as follows
“A project is a problematic act carried to completion in its natural setting”-Stevenson
“A project is a whole-hearted purposeful activity proceeding in a social environment”-Kilpatrick
“A project is a bit of real life that has been imported in to the school”-Ballard
Basic principles of the project method
1. The principle of Purpose
The activity performed by the pupils must be significant and of interest for them. It must be purposeful and combining life with learning.
2. The principle of Activity
The pupils are naturally active. Opportunities should be provided for them to be active and do things for themselves. They must be kept active mentally as well as physically and must bear the maximum responsibility. The project method aims at making the pupils active throughout.
3. The principle of Reality
This method aims at reproducing real life situations in to the school. Pupils are given opportunities to exercise their powers in real life situations.
4. The principle of Freedom
The desire for any activity should be spontaneous and not forced by the teacher. It should grow out of pupil’s own purpose and need. They should free to do and express themselves.
5. The principle of Utility
Knowledge gained should be useful and practical. The project method ensures practical utilityof the knowledge gained.

Major steps of the project method
1. Creating the situation (Providing a solution)
The first task of the teacher under the project method is to provide for such a situation where in the pupils feel a spontaneous urge to carry out a particular project according to their needs and interests. The teacher has to discover the interests needs tastes and aptitudes of children. He may draw the pupil’s attention to the projects in mind through informal conservation or discussion as taking out children outside the school. Thus pupils are brought face to face with the situation.
2. Choosing the project (Selection of the project)
The pupils should themselves choose the subject. Self choice leads to better results and entail self satisfaction. Pupils select anyone, discuss the various projects, rejects some, explain others and thus come to a decision. The teacher should see that the project chosen are of great utility and satisfy the real need of the pupils and are within their capacity to be successfully carried out.
3. Planning
Pupils should themselves do the planning and the teacher to guide them. Discussions may be held and each student should be encouraged to express his views and suggestions. The teacher may point out the difficulties involved in the carrying out of the project. Resources and limitations should be discussed. After such oral discussion, the detailed plan may be written up by the students in their project book.
4. Carrying out the project (Executing)
It is the most important and longest step, and therefore needs a great deal of patience on the part of the teacher and the students.
When the plan is ready, pupils are to put it to practice. Students themselves should distribute the various items of duties among themselves according to individual interest and capacities. Every student must contribute something towards the successful completion of the project.
A chain of activities are to perform by the students. They are busy in collecting information, visiting various places and pupils, looking up maps, writing letters, referring library books, observing specimens, studying history, keeping accounts, calculating prices, inquiring rates, measuring lengths and areas. The teacher should guide the students provide necessary information and help them on right lines.
5. Evaluating
No project is complete unless the work done in it is evaluated. Students should assess their activities; whether they have been carried out in accordance with the plan choked out or not, mistakes committed are noted.
6. Recording
The teacher should keep a complete record of work how they planned what discussion were held, how duties were assigned and finally criticism of their own work and some important point for future.
Kinds of project
1. Producers type -Students construct materials-models of garden, collect specimens, flowers, seeds etc.
2. Consumer type-Students get experience and enjoy by conducting excursions.
3. Problem type-Solution to problem to be found out like cause of an epidemic, how to purify water etc.
4. Drill type-Efficiency in some activity like skill in swimming, manual work etc.
Merits
1. The method is in accordance with psychological laws of learning such as law of readiness, law of exercise and law of effect.
2. It promotes co operative and group interaction.
3. It gives raining in the democratic way of living and learning.
4. It teaches dignity of labour and the pupils develop respect and taste for all types of works.
5. Correlation of subjects is achieved.
6. It develops initiativeness and self activity.
7. It affords opportunity to develop keenness and accuracy of observation.
8. It makes learning natural, spontaneous and interesting.
Demerits
1. Projects absorb a considerable amount of time and can be used as a part of science work only.
2. It gives the children superficial knowledge of so many things but leaves an insufficient basis of sound fundamental principles.
3. Planning and carrying out projects involves much more work on the part of the teacher than with their usual methods
4. Larger projects in the hands of an inexperienced and unskilled teacher lead to boredom.
5. It pre-supposes that the teacher is a master of all subjects and has an alround knowledge of everything to impart correlation. But it is practically impossible.
6. Text books written on these lines are not available.
G.  HISTORICAL METHOD
In this method instead of presenting scientific principles and theories in heir finished form, they are taught by tracing their development through successive stages in their historical order. This method helps the teacher to fill the gap between the current knowledge and the past knowledge to a great extent. This will reveal the evolutional nature of scientific knowledge to the pupils.
Merits
1. The historical method enables the teacher to develop the pupils correct attitude towards science. That is a grand expression of human spirit.
2. The method enables the teacher to adapt his teaching procedure to the child’s level of understanding
3. The method helps the pupils to enjoy the real feel of science.
Demerits
1. The path of scientific progress is extremely long and if the historical order of development is rigidly followed it would result in much wote of time.
2. The pupils of the present day possess good knowledge of the historical development of scientific topics and for them it is unnecessary to follow this approach.
 CO OPERATIVE LEARNING
Co operative learning, as the name suggests, stands for a learning process or learning strategy I which students are provided with opportunities to learn by themselves in a group in co operative way. They share all the information among themselves and help each other in gaining the required knowledge, understanding the application of one or other aspects of the content material or course units included their syllabus.
Definition
Co operative learning is defined as teaching-learning strategy in which the students of a class encage themselves in a variety useful learning activities in co operative and non competitive environment by forming a number of teams, each consists a small number of students of different levels of ability for their understanding of a subject.
Basic assumptions of co operative learning
1. Co operative learning believes in making the teaching learning process learner- centered rather than content or teacher centered.
2. It advocates a constructivist ideology for the better the teaching-learning outcomes by encouraging students to formulate their own constructs and way of understanding the content material.
3. It believes in redefining the role of teacher as distinct from a lecture; expert of subject knowledge. The teacher’s role is that of a facilitator who helps his students  in their co operative learning.
4. It advocates an interactive teaching learning environment instead of mere lecturing and demonstration on the part of the teachers. Here the responsibility for learning is thus shifted to students instead of teacher’s efforts for making his students learn by resorting to the other tactics.
5. It emphasizes social learning by assuming that learning take place better in a social situation and group environment rather than individually in isolation.
6. It assumes that children learn better in known-competitive anxiety free co operative environment than in a competitive stressful environment available in the traditional classroom situations.
7. It believes in group efforts and co operation among learner in place of individual efforts of competition.
Co operative Learning Approaches:
1. STAD (Student-Teams-Achievement-Division)
2. The Jigsaw classroom
3. Learning together
4. Group investigation
5. Co operative scripting
Merits
1. Co operative learning groups are more or less permanent depending on the conditions in the given classroom.
2. Teacher has to set the stage, tone and hopefully, a satisfying and rewarding environment.
It develops conceptual achievement and critical thinking.
4. Co operative relationship is established.
Demerits
1.       Difficulty in selecting the learning task.
2.       Evaluation in terms of outcome and procedures is difficult.
3.       Heterogeneity of the group.



Distinction between Traditional Learning Group and Co operative Learning Group
Traditional Learning Group
Co operative Learning Group
1.No interdependence
Positive interdependence
2.No individual accountability
Individual accountability
3.Homogeneous
Heterogeneous
4.One appointed leader
Shared relationship
5.Responsibility only for self
Shared responsibility for each other
6.Only task emphasized
Task and maintenance emphasized
7.Social skills assumed and ignored
Social skills directly taught
8.Teacher ignores group functioning
Teacher is an observer and intervener