Physics can put students on their own intellectual feet

By D.K. Nachtigall

SINGARAJA, Bali (JP): Physics appears to be boring, meaningless, and not useful for daily life. The reason is that most physics teachers focus upon providing the subject matter on definitions and formulas in physics. They do not provide learners with understanding about physics. Memorization still has priority over application of physics to meaningful events. Therefore, rote learning earns good marks, but thinking is often neglected.

To me, the main goal of teaching physics in school is to put our students on their own intellectual feet and show them how to walk for themselves. Since this has not been conducted very much in physics classes, the outcome of physics classes in terms of thinking ability are meager improvements. Major improvements can be only made possible when physics teachers adopt a new self- concept.

They should no longer be a god-like information provider, who indoctrinates pupils with concepts they do not understand. Instead, physics teachers should act as helpers for further developments, both intellectually and ethically. This will also include the three insights of teaching and learning, as follows: (1) to present subject matter is not teaching, (2) to store stuff away in the memory is not learning, and (3) to memorize what is stored away is not proof of understanding.

The role of a helper for development implies that the teachers should become aware of the existence of preconceptions in the minds of students. The minds of students who come to a physics class for the first time are not like empty bottles into which "the physics" can be poured.

They are already occupied by naive world views, simple rules of belief, primitive experiences and practical "working hypothesis", by means of which students make sense out of their environment. We call them preconceptions because they exist before we give our physics classes. The concepts on which they are based, in most cases, do not conform with the physics concepts.

These preconceptions are deeply rooted in the students' minds. They are truly "private mental property" because their generation is biographically determined. They are sometimes contradictory to each other, and often unconscious, but they are a common tool to handle the events in the daily life-world. When students learn physics, their preconceptions must be transformed into physics concepts. When we want to do this with success, then we must:

* make the individual preconceptions conscious to the students in the class,

* confront them with each other,

* observe, reflect, and compare,

* show contradictions among them,

* demonstrate that they often fail, in particular when we want to make predictions,

* introduce the physics concept, the idea first, the definition later, and finally, the mathematical representation which must always be interpreted,

* let students feel a mental conflict because the physics concept is different, and often counterintuitive,

* show that the physics concept is more powerful, explains more, has a longer range of validity and allows -- first of all -- quantitative predictions,

* create, in general, an environment whereby the students can develop strong conceptual understanding of physics through examination of everyday phenomena.

Teachers often claim that it is too time consuming to discover and transform the preconceptions. They must cover textbook content and syllabus and cannot discuss the "crazy", wrong, "stupid" ideas appearing in the preconceptions. So, they ignore the preconceptions, or try to destroy them in saying that they are nonsense and that the only truth in physics is what is written in their textbooks. This must be learned, and everything else shall be forgotten.

Both "strategies" fail because physics concepts, taught in this way, are normally not or poorly understood and the homemade preconceptions survive all physics courses given in this unscientific way. The result of this kind of "giving lessons" is that students just memorize physics vocabulary but remain on the preconceptional level of understanding. When they have to solve real problems in physics, they express their preconceptional thinking by means of physics vocabulary and the result is what we call misconceptions. All students come to their first physic classes with preconceptions. Being taught in the described way means most of them leave school with lots of misconceptions.

This is certainly not the goal of teaching and learning physics. In my course presented to future physics teachers at STKIP Singaraja, Bali, I have given many examples of preconceptions; have shown how one can discover and transform them into physics concepts; have demonstrated that even physics teachers may have -- and teach -- misconceptions; and have provided the students with strategies to overcome them. I think that improvement of education urgently requires the implementation of such a course into the curricula of science teacher education.

Dr. D.K. Nachtigall is a visiting professor of physics education from the University of Dortmund, Germany. He has been working for four weeks at STKIP Singaraja, Bali.