Alternative conceptions underpin some, but not all, learning difficulties
Keith S. Taber
I recently wrote here about a paper published in a research journal which used a story about the romance between two electrons, Romeo and Juliet, as a context for asking learners to build models of the atom. (I thought the approach was creative, but I found it quite dificult to decode some aspects of the story in terms of the science).
Read 'Teenage lust and star-crossed electrons'
Misconceptions misconceived?
But something else I noticed about that study (Aquilina et al., 2024) was that the authors listed a number of 'misconceptions' that their teaching approach was meant to address (see the Table reproduced above). These were:
- Students, after studying planetary and Bohr's atomic models, cannot move beyond them easily.
- Students rarely reflect on and/or understand the need for the development of new atomic models.
- Students find it difficult to associate spectral lines with transitions between energy levels.
- Students do not describe photon emission processes properly.
- Students do not clearly understand the concept of an orbital.
- Students find it difficult to understand atomic quantum-mechanical models.
But none of these actually seemed to be misconceptions.
To be clear, I think
- all of these points are pertinent to the research; and they reflect
- challenges to the teacher, and
- learning difficulties experienced by many learners.
But they are not misconceptions.
What is a misconception?
There is a very large literature reporting student misconceptions, or alternative conceptions, in science subjects.1 A misconception, or alternative conception, is a conception that is judged to be inconsistent with the scientific account (or the version of the scientific account presented in the curriculum). The points listed in Aquilina and colleagues' table are not conceptions, so cannot be alternative conceptions – just as a postbox cannot be a red car, because it is not a car; and nor can Boyle's law be a refuted theory, because it is not a theory; and a mushroom cannot be a leafless plant, because it is fungi not plant.
So, what is a conception?
We might understand a conception to be one facet of a concept (Taber, 2019). Consider a student has some ideas about atoms. We might consider the learner's concept of the atom to be the collection of all those ideas about atoms. Imagine a learner thinks:
- atoms are very small
- an atom contains a nucleus
- atoms contain electrons arranged in shells
- there are many different types of atoms
- gold atoms are gold coloured
- everything is made of atoms 2
- an exploding atom can destroy a city
If this was the full extent of their ideas about atoms, we might collectively see this list as comprising their atom concept. We could represent it by drawing a concept map showing how the learner sees 'atom' to be linked to other concepts such as 'nucleus', 'electron', etc.
But we might consider each one of these separate statements to be a conception.
There are complicatons:
- A person may have (implicit / tacit) 'conceptions' that they could not easily put into words to express as statements. (A researcher might elicit what a learner is thinking and represent it as a sentence, but for the learner it may be more a vague intuition that they only put in words in response to the researcher's questions.)
- A person may also show different levels of commitments to conceptions – perhaps our hypothetical learner is pretty certain that atoms are very small, but only has a hunch that gold atoms are gold coloured. Perhaps the learner was told by a friend that an atom bomb that is powerful enough to destroy a city is based on exploding a single atom at its centre – and our learner remembers this, but is actually very sceptical.
(Would anyone think that latter idea was feasible? Perhaps not, but an episode of a popular TV sci-fi series featured a weapon that could destroy whole worlds from a great distance – based on the action of 8 neutrons! Presumably the scriptwriters thought viewers would accept this. Read 'How much damage can eight neutrons do? Scientific literacy and desk accessories in science fiction').
What makes a conception alternative?
We usally say a learner has an alternative conception when they hold a conception which is inconsistent with (so alternative to) the scientific account. A great many such alternative conceptions have been elicited in research that explores people's thinking about science. Much of this work has been undertaken with science learners, but some simply with people in the general population (when alternative conceptions may be termed as 'folk science' or 'urban myths'). Here are just a few of the examples discussed elewhere on this site:
- plants only respire when it is too dark for them to photosynthesise
- metals cannot be evaporated/boiled
- planets stay in stable orbits because the force of gravity is balanced by a centrifugal force pulling them outwards
- chemical reactions occur because atoms want to fill their shells
- quinine contains rare earth compounds
- E=mc2 means mass can be changed into energy
These are 'alternative' because they are contrary to the scientific account, and they are significant to science teachers because they are contrary to the target knowledge the teacher is expected to teach to students.
One reason to perhaps prefer the term 'alternative conception' to 'misconceptions' is that the latter term may seem to imply the outcome of misunderstanding teaching. Alternative conceptions certainly can be linked to misunderstanding teaching, but often this occurs because the learner already has an intuitive idea that is contrary to the science, and this leads to them misinterpreting teaching. But consider this example:
- an atom of an element in the first period has a full shell with two eletrons, all other atoms would need to have eight electrons in the outer shell for it to be a full shell
This is an alternative conception that learners sometimes do hold, whereas eight electorns only counts as a full shell in period 2 (Li, Be, B, C, N, O, F, Ne) and not for any of the other elements. So, a chloride atom (electronic configuration 2.8.7) does not have a full outer shell when it joins with an electron to become a chloride ion (2.8.8).
But I have seen school textbooks aimed at secondary levels learners (c.14-16 year old students) that actually state quite clearly that all atoms, apart from H and He have a full outer shell with eight electrons. If a learner had read that in the textbook issued by the school, and so believes it to be so, then they have not misconceived what they read – they have accurately understood the intended meaning. But it is still an alternative conception ('misconception').
Learning blocks and misconceptions
So, something cannot be an alternative conception (misconception), unless it is both a conception, and counter to the scientific account. But there are other reasons a learner may struggle to understand the science in the curriculum.
A learner may lack specifc prerequisite background knowldge needed to make sense of a new idea; or the learner may not appreciate that cetain prior knowledge is meant to be applied in understanding the new material. Learners may indeed misinterpet teaching due to an existing alternative conception, but they may also sometimes make an unhelpful association with unrelated prior learning. (That is, they interpet teaching in terms of some prior learning that they think is related, but which from the scientific perspective is not relevant.) Sometimes that may relate to how scientific terms may be understood through the learner's language resources (such as assuming a 'neturalisation' reaction will always lead to a neutral product becasue that's exactly what a reasonable person might expect 'neutralisation' to mean!) or it may relate to not appreciating the limitations of a teacher's model, or to how an analogy or metaphor (e.g., electron shell) is intended to be figurative, not literal.
Learners may not always understand teaching as intended
Read about types of learning impediments that can interfere with student learning
So, alternative conceptions are indeed very relevant to the challenge of teaching science, but not all learning difficulties are due to alternative conceptions; and certainly not all learning dificulties should be labelled as 'misconceptions'.
Beyond misconceptions
So, what about Aquilina and colleagues' list of supposed 'misconceptions'?
- Students, after studying planetary and Bohr's atomic models, cannot move beyond them easily.
- Students rarely reflect on and/or understand the need for the development of new atomic models.
- Students find it difficult to associate spectral lines with transitions between energy levels.
- Students do not describe photon emission processes properly.
- Students do not clearly understand the concept of an orbital.
- Students find it difficult to understand atomic quantum-mechanical models.
There are a number of well-recognised issues here. Two in particular stand-out.
The unfamiliar abstract
For one thing the subject matter is unfamiliar and abstract. People can only understand teaching if they can link it to existing experience or prior learning. Teachers have to find ways 'to make the unfamiliar familiar'. (This is why Aquilina and colleagues devised a narrative based on a tragic love story that they expected the students to be familiar with.)
Read about teaching as making the unfamilair familiar
But learning about the abstract in terms of the familiar only moves a learner so far when the familiar is only a little like the target. Learners know about shells, so can imagine electrons in shells – but electron shells are not really like more familiar shells (such as those that protect snails and cockles or bird's eggs). Learners can imagine electrons spinning like spinning topics, but electron spin is not like that – the electron does not spin.
The behaviour of quanticles, quantum objects, is quite unlike the behaviour of familiar objects. An orbital is not really an object at all, but more a description of the solution of a mathematical equation – those diagrams showing the different atomic or molecular orbitals are a bit like the map of the London underground: schematic representations that are useful for some purposes, but not realistic images of the orbital/rail line.
Acquiring model nous (epistemologial sophistication)
The second issue relates to epistemological niavety, which comes from not appreciating the subtle nature of science. If we teach students that an atom is like THIS (say, electrons orbitting a central nucleus like planets orbiting the sun), why shoud we then be surprised that students think that is what an atom is like – and so then struggle to understand why we are now teaching them the atom is quite different from this? The defence that we did point out this was a model is only convincing if we are sure the students understood what a scientific model is.
We might describe thinking that electrons in atoms have definite trajectories as being a 'misconception' – but if we have taught such a model then the learner's real misconception is in thinking that such a model is meant to be a realistic representation. If we never taught them that the model was something other than a scale replica of an atom, then this is a 'pedagogic learning impediment'. That is, the student is only guilty of learning what they have been taught!
Perhaps more attention to this aspect of the nature of science throughout school science might avoid this problem. Imagine that from a young age learners had regularly been asked in their science lessons to:
- devise different models and representations of various scientific phenomena
- identify the strength and limitations of different models (both those produced by learners, and mulitpile representations presented by the teacher)
- discuss why having several different (imperfect) models might sometimes be useful
- be asked to choose between alternative models/representations for different specified purposes
In contexts where science has tended to be taught as though it offers a single, realistic account of phenomena, then we should not be surprised
- that students do not see the need to move beyond the models they have been taught (they consider them as more like scale replicas than theoretical models)
- nor indeed when they complain they have put a lot of effort into learning models they now feel they are being taught were wrong all along!
Learners' alternative conceptions are a major impediment to learning school and college science. However, learning of abstract ideas requires learners to make sense of teaching in terms of the interpetative resources they have available – and that is often challenging enough even when they have no existing alternative conceptions in a topic.
Read about the constructivist perspective on learning
Work cited:
- Aquilina, G.; Dello Iacono, U.; Gabelli, L.; Picariello, L.; Scettri, G.; Termini, G. "Romeo and Juliet: A Love out of the Shell": Using Storytelling to Address Students' Misconceptions and Promote Modeling Competencies in Science. Education Sciences, 2024, 14, 239. https://doi.org/10.3390/educsci14030239
- Taber, K. S. (2014). Student Thinking and Learning in Science: Perspectives on the nature and development of learners' ideas. New York: Routledge.
- Taber, K. S. (2019). The Nature of the Chemical Concept: Constructing chemical knowledge in teaching and learning. Cambridge: Royal Society of Chemistry.
Notes:
1 There are a number of other related terms used in the literature, such as intuitive theories and preconceptions. Sometimes these different terms refect subtle distinctions (so preconceptions refers to alternative conceptions a learner has prior to being taught anything about a topic). But, in practice, there is no real consisitency in how various terms are used across different authors.
I try to reserve the term alternative conceptual framework for more large scale conceptual structures than discrete alternative conceptions. (But again, the terms are sometimes used interchangeably) So, for example, the 'octet' framework is a network of related conceptions built around the core alternative conception that chemical change is driven by atoms needing full electron sells or octets of electrons:
Read about the octet alternative conceptual framework
2 A teacher might want to ask students what they means by their words. If a student suggests they believe that everythings is made of atoms, or everything is made from atoms, then this may be a canonical understanding, or an alternative conception:
| motto | is a short-hand way of suggesting | alternative conception |
| everythings is made of atoms | all material substances found under normal conditions can be shown to contain atomic cores surrounded by electrons | if we could examine all materials we would find they are comprised of lots of discrete atoms just stuck together |
| everything is made from atoms | we can envisage that any substance could be built up by chemiclly joining together a certain number of atoms of various elements – all molecules and other structures can be imagined as being built up from atoms | chemical reactions produce different substances by starting with lots of atoms of the relevant elements |
The book Student Thinking and Learning in Science: Perspectives on the Nature and Development of Learners' Ideas gives an account of the nature of learners' conceptions, and how they develop, and how teachers can plan teaching accordingly.
It includes many examples of student alternative conceptions in science topics.
