Science Teaching II
Mmethods that are frequently used by science teachers include:
- Lecture or “talk – chalk ” method
- Demonstration method
- Discussion method
- Discovery (guided and unguided) methods
- Project method
- Field trip method
- Laboratory / Investigation method
Lets discuss these methods.
Lecture / Expository Method
About eighty percent of the scientific information, principles, theories, hypotheses and laws, that pupils acquire from their science teacher come through the lecture method. Since our educational system puts much premium on paper qualifications earned through public examination (WASCE, NECO, NCE, etc), science teacher embrace this method of teaching. With this method, the teacher is the principal actor who disseminate large amount of scientific fact to the pupils who are either passive or slightly involved in the lesson. For this method to be effective, the teacher must have clear and good command of language. Teacher should be able to write clearly and boldly on the blackboard.
Advantages of Lecture Method
- The method is economy in terms of and effort. It is less cumbersome for the teacher and not much energy is required.
- It leads to easy coverage of the syllabus. Since much scientific facts can be disseminated within a short period of time, the coverage of the syllabus is easy.
- The method is suitable for a large class when the population of the students in the class in high, this method is often used.
- The method is economical interims of fund, the teacher need little fund to use this method.
Demerits of Lecture Method
- It does not promote meaningful learning of science as it appeals to only the sense of hearing. Since other senses are not involved, the sense of hearing alone leads to forgetting.
- The method does not put into consideration “individual differences” among the pupils. Since most classes are heterogeneous (mixed ability) not all the students can understand the lesson.
- The method promotes boredom and tiredness. The most viable limitation of lecture method is that pupils quickly become restless and disruptive.
- The method encourages rote learning. This method does not encourage meaningful learning since only sense of hearing is involved.
Demonstration method is the act of displaying something. This method is used by the teacher when the equipments are not sufficient to go round the students or when the experiment is delicate for the students to handle. An example is the reaction of sodium metal with water which is explosive if handled by students. Demonstration is different from laboratory method because the experiment is usually done by the teacher or sometimes performed by students in small groups.
For demonstration method to be effective, the teachers should do the following:
- Demonstration experiment should be attempted only if the teacher is convinced that it will succeed. When a demonstration fails it makes pupils to have less confidence on the teacher and science as a course.
- When demonstration is used for a large class, the class should be divided into smaller groups to facilitate good visibility.
Advantages of Demonstration Method
- Demonstration method can be used to introduce a lesson and to climax a lesson. It is an attention inducer and good motivator when used at the beginning of the lesson.
- The method can be used to teach a large class when the equipments are not sufficient. Much time is saved when the teacher demonstrate an experiment to the pupils.
- Through demonstration, the teacher shows how to avoid breakages, and accidents to the students.
- Dangerous experiment that cannot be handled by students is shown to the students through demonstration by the teacher e.g. investigating the force around a magnet by using iron fillings.
- It encourages students to inculcate positive attitude towards science. When important experiment is demonstrated by the teacher; students got exited.
Demerits of Demonstration Method
- It does not allow students to develop manipulative skill and the students do not satisfy their psychological need to do the experiment individually.
- Visibility is usually poor when demonstration method is used by teacher. Pupils always have difficulty in seeing details of the object being demonstrated.
- Demonstration method does not encourage meaningful learning of scientific concepts/principles since students are to observe only.
- For a large class, demonstration does not allow easy coverage of the syllabus, since the teacher need to divide the class into smaller groups when demonstrating, much time is often wasted on a topic.
- Demonstration method encourages poor class control. In a large class, when the teacher is busy demonstrating an experiment to a group, the control of the class becomes less effective.