Misconceptions in science education

INDEX

Introduction

Methodology

Results 1

Results 2

Discussion

Final conclusions

 

Educational research

This work was realized during my PGCE (post-graduate certificate in education) course, when I was teaching in English secondary schools. The title of this research is:

Misconceptions in science education

Discussion of results

-Comments on particles

The particle model should be seen by most pupils  as very “natural”, in the way that it follows a structure  that is already observed in languages and maths. It is a direct application of the fragmentary 7view of the world  , which is deeply rooted in the mind of most people, including scientists.

Most modern languages use the structure subject-verb-object, where there is a separation between the thing that acts and the thing that is acted upon . This shows how the fragmentary approach influences our thinking at various levels. Furthermore, an analogy can be drawn between the organization of different elements to form substances and the organisation of different letters to form syllables2. The syllable will form words (materials) that will form sentences (objects).

In maths, the idea of dividing a big problem into small manageable chunks (Cartesian method) has successfully being applied for thousands of years and is a triumph of the fragmentary approach.

Hence, the particle model should be assimilated easily by pupils, but that doesn’t seem to be the case. As the results have shown, it is not completely clear for them  what are the particles doing and why.
The simple idea that the whole of reality can be represented by  tiny chunks of matter that move about in the void seems a bit strange to most pupils as the interviews have shown.

Also , I believe that topics more recent advances of physics like antimatter should be included in the National Curriculum, as it happened to certain areas of biology like cloning or biotechnology. This way, pupils would be able to recognise that particles are not the ultimate substances that form the world, because they can be created and  annihilated 7  . That would also expose one of the biggest mysteries of science: why are there more anti-mater than matter? The scientists of tomorrow should assimilated these new and revolutionary views of the world from an early age, so that their minds can be free from misconceptions.
In addition, the view that “the whole world is constituted of nothing but an aggregate of separately existing atomic building blocks 7” has been proved wrong in modern physics experiments. So , if a bright kid wants to discuss these ideas, the teacher has to be very careful and try to leave his/her mind open instead of imposing the particle model as an absolute truth. That is particularly important for pupils that have an inclination for the natural sciences.

Curiously , the problems observed with the understanding of the concept of force and the concept of particles seem to be related. The link between the two is a concept that doesn’t seem to be very familiar to pupils: vacuum.

Firstly the concept of force. A body will keep moving at a constant speed if there are no forces acting on it. This only happen is a frictionless environment like vacuum. It is a bit difficult to assimilate this concept when you live in a world where friction is everywhere and things don’t  move too far unless there is a force (engine or something) acting. Secondly, the particle model: Particles move around a vacuum . Having assimilated the concept of vacuum, it is easy to understand that there is nothing between particles.

Apart from introducing the concept of vacuum , the teaching of the particle model can be improved by the use of  computer animations, to make evident the movement of the particles. Faster particles can be shown for higher tempearatures.  A further improvement would be to represent different forms of particles, which can have different colours or different sizes. The representation of molecules moving around (vibrating along the bonds) would be excellent.

The use of models is essential in the teaching of particles, because they cannot be seen or experienced directly. Pupils may not be used to using models or teaching models, so that they confuse things.               The particle theory is an excellent opportunity to introduce the use of models and analogies in the teaching of science. It must be made clear to pupils the limitations of the teaching model. Also, pupils shouldn’t confuse the teaching model used (snooker balls, for instance)with the actual particle model.

-Plants and photosynthesis

The questioning about where the plants take their biomass from extended to even more basic concepts like energy and particles. Some students answered that the mass comes from photosynthesis, and I had to ask some more questions to make sure that there was understanding there:

 It is seem difficult to identify that air provides the basic material to build the plant, although they knew  the equation for photosynthesis (at least the word equation).

Synthesise  means to build something. Why is so difficult to see that photosynthesis build a plant?

Perhaps it should be pointed out to students that glucose forms different polymers, which can assume very different appearances. So, the structural materials of a plant are hard substances (polymers)  like quitine. Pupils are used to talk about polymers when learning about crude oil and the refining industry, but they don’t often use the concept in a biological context. Different polymers of glucose, the ultimate building material of plants, can perform various jobs. Starch is probably the only natural polymer pupils certainly know about, from the context of digestion.

Glucose seem to be associate mainly to nutrition/respiration and not to building blocks. That is more or less the case for animals but definitely not for plants.

Photosynthesis is a key process and it must be fully understood.

It is crucial that teachers promote learning by understanding instead of giving pupils “knowledge packages”  (Paulo Freire, Education as a practice of freedom). That will be the next revolution in education.

Is it possible that a “low achieving student” has less misconceptions than a top set pupil?  I think it is possible, in a situation where the assessment methods used measure the amount of information received and not the level of assimilation of the material. The common assessments often fail to measure problem solving skills and aptitude for research as well.

A child may be told that is doing very good progress, although a lot of his/her learning is not a learning by understanding. Having a good memory and doing substantial effort, this pupil will be able to perform very well on the courses. However, this learning process will reach a point above which further progress will only happen at a  slower rate.Finally, it will reach a point where it cannot take him/her any further. This occurs specially in the learning of maths and science. It may cause disappointment and  frustration. The presence of misconceptions “may inhibit further conceptual
development “   (DfES,2002).

Learning by understanding very often loses space to learning by obedience, learning by respect, by memorization.

Another  reason for the difficulties observed may the fact that many of the pupils interviewed have not yet reached formal operational thinking , so that they cannot use abstract models to explain and predict8 . There were a few who didn’t have notions of conservation properly assimilated.