Science Learning Doctors

Diagnosing 'learning bugs': Deficiency learning impediments


The typology of learning impediments is intended as a diagnostic tool for thinking about where science learning 'goes wrong'. It is  a model of the different types of 'learning bugs' that may occur when our teaching does link to students' thinking in the ways we intend.

One category of learning impediment is deficiency learning impediments:

NULL LEARNING IMPEDIMENTS occur when the intended learning may not take place because student is unable to make sense of the teaching in terms existing ideas
This may be because the student has never acquired necessary pre-requisite knowledge, i.e.
a deficiency learning impediment



Not having a language for describing quanticle behaviour: If particles don’t ‘try’, then what do they do?

Not having a language for describing  quanticle behaviour: If particles don’t ‘try’, then what do they do?

Peter [7.1], a year 7 student, told me that:
“Gases, they try and fill whole room, they don’t, like liquids, they stay at the bottom of the container, but gases go fill, do everywhere and fill, try and fill the whole thing.”
When asked “Why do they try and do that?” he replied that “Erm, I’m not sure.”
I suggested some things that Peter might try, and asked “so when the gas tries to fill the room, is it the same sort of thing, do we mean the same sort of thing by the word 'try'?” Peter appreciated the difference, and recanted the use of ‘try’:
"No, I think I phrased that wrong, I meant that it fills the whole area, 'cause it can expand."
However, it soon became clear that Peter’s use of the term came easily, despite accepting that it was misleading
I: Okay. So it’s not, the gas does not come in and say, ‘hm, I think I’ll fill the whole room’, and try and do it?
Peter: No, it just does it.
I: It just does it?
Peter: It tries to get out of everywhere, so if you put it in the bottle, it would be trying to get out.

And later:
I: …are there particles in other things?:
Peter: liquids, yeah there is particles in everything, but liquids the particles move quite a lot because, well they have, oh we did this this [most recent] lesson, erm, they have energy to move, so they try and move away, but their particles are quite close together.
I: What about the gases?
Peter: The gases, their particles try to stay as far away from each other as possible.
I: Why is that? Don’t they like each other?
Peter: No, it’s because they are trying to spread out into the whole room.

And later:
I: …and you said that liquids contain particles? Did you say they move, what did you say about the particles in liquids?
Peter: er, they’re quite, they’re further apart, than the ones in erm solids, so they erm, they try and take the shape, they move away, but the volume of the water doesn’t change. It just moves.
I: What about the particles in the gas?
Peter: The gas, they’re really, they’re far apart and they try and expand.
Peter had only learn about particles recently in science, but seemed to have already developed a habitual way of talking about them as conscious agents that strived to fill rooms, escape bottles, and take up the shape of containers. To some extent this is surely a lack of familiarity with objects that can have inherent motion without having and external cause (like a projectile) or internal purposes (like animals) and/or having a suitable language for talking about the world of molecular level particles (‘quanticles’).  Such habits may be harmless, but it is a concern if such habitual ways of talking and thinking later come to stand for more scientific descriptions and explanations of natural processes.




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Typology of Learning Impediments


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