The Constructivist Classroom

The various Twentieth Century schools of epistemology vary greatly in their assumptions about learners, learning, and the nature knowledge. The constructivist view of education is radically different from the behaviourist and the cognitivist views.  In the constructivist view of teaching and learning, knowledge is not communicated by the teacher to the learner.  Constructivists believe that learners construct their own meaning of the world and that instructional designers should focus their efforts into coding new information in a form that allows it to be integrated into the learner’s existing mental models of understanding.   Constructivists view learners as active, not passive.  Exposing learners to new experiences generates perturbations.  These are forms of mental disquiet that require the learner to reconcile the new information with existing knowledge. Learners construct their own understanding of the world based on their experiences of it.  Individual prior experience of the world and individual prior understanding of it are central to the constructionist view of learning.

In a constructivist classroom teachers take on the role of guides and they attempt to create situations in which students can discover knowledge.  This can be challenging for students and teachers.  College students find it particularly challenging because most were successful in cognitivist classrooms where they developed techniques for recalling answers to questions.  Since they had to be good cognitivist students in order to get to college in the first place, many find any switch to a constructivist model difficult, and even unfair.

A few years ago I taught a Computing Ethics module at CIT and attempted to use a constructivist approach.  Following explanation of various basic principles I presented students with case studies and ask them to discuss the relevant issues with each other and to recommend the appropriate courses of action.   For example, we discussed a Cyber Ethics variant of Foot’s classic trolley thought experiment.  A tram or trolley is careering out of control along a track and is on course to kill five people.  Pulling a lever will switch the track and send the tram along the path of only one victim.  Utilitarian ethics suggests that choosing to kill one person to save five is clearly the most ethical choice.  Most students in the class shared this view.  The fat man variant of the problem allows the trolley to be stopped by a sufficiently heavy weight and places a fat man on the platform.  When asked if it was ethical to push the fat man in front of the tram, fewer students were comfortable with the utilitarian view.  A trap door variation of the problem, illustrates to students how technological mediation of our actions can alter how we feel about them.  Many students who were uncomfortable with pushing the fat man in front of the trolley, were happy to push a button that released a trap door under him, placing him in the path of the trolley.  Students who believed they held utilitarian views on the taking of one life to save five, found that they changed their minds depending on the scenario even though the basic equation was unchanged.  Break down cases such as these challenge students’ understanding.  They generate what constructivist call perturbations or to use Piaget’s term disequlibrium.
[taken from my submission for EDUC9026]

A meta-study by Alfieri et al (2001) found that discovery based instruction does indeed enhance learning, but the authors also identified some of the issues that must be considered.  Does the process by which students can learn for themselves need to be taught?  I believe that it does, particularly in Ireland, where admission to college requires a great deal of rote learning of the right answers.  At CIT the Creativity, Innovation, and Teamwork module was devised specifically with this in mind. However it is not certain just how much guidance students should be given, and which kinds of knowledge can be acquired by discovery based techniques. Kirschner, Sweller and Clark (2006) concluded that constructivist approaches to education are untested and that without strong guidance students often fair worse.  While hard-line constructivist might be inclined to believe that students are capable of learning everything for themselves, I don't think anyone at CIT would ever go that far.  But it's clear that the constructivist view does have something to offer, and for most of us represents a step in the right direction.

Micro-teaching Session

Soliciting students to identify their preconceptions or world views, and then challenging them is a classic constructivist approach to learning.  It can make for a very interesting class, but in content driven module it may not always be appropriate or practical.  For my micro-teaching session I chose to explain the RGB colour system used for specifying colour, because people have everyday experience of colour, but rarely think about it.  I wanted to devise an activity that would explain the topic, but also engage the students and get them to think.  I was particular keen to use the opportunity to get out the rut I have worn for myself and to walk around the classroom.

In the first two slides I explained that digitising colour is just a matter of putting numbers on it, and putting numbers on it first requires finding some kind of order.  I think I posed the initial question quite well, and stuck with that main issue for the entire session.  The micro-teaching session was only 10 minutes long, but I don't think it follows that in 50 minutes, one should attempt to do 5 times as much.  Lecturers often worry about getting through all the course material in a module, but where practical I think it is best to make a few fundamental points really well.

I gave students grey chips of paper and asked them to put them in order.  I really wanted an activity that required students to do something with their hands.  As expected the students placed them in a line starting with the brightest at one end and the darkest at the other.  I explained that when digitising shades of grey, computer systems do largely the same thing.

Next I posed the same problem to students but with colour chips.  Putting colour chips in order is a much more difficult task.  As I walked around, I noticed that most students found it hard to find an organising  structure for the colour they had.  The task I had given then was actually impossible to complete with only two dimensions, and only one student even tired two.  Most continued, as they had done withe the grey scale chips, to work in one dimension.  I was worried about giving students an impossible task.  But I think the problem they faced was one that they could easily understand, but had never actually considered.  Challenging students with a problem that they cannot solve, creates a question that begs to be answered, and I think that's a great way to engage students, to get their attention,  and to place the lesson content in a meaningful context.

At the end of the class students were asked to match the RGB values on the envelope they were given to one of the colours inside.  This was a good way to test understanding.

In general I was pleased with how the micro-teaching session went.  I felt the activity worked well.  The big lesson for me was that it's important to take some risks if you want to engage students.  I think the challenge for an organisation like CIT is to create a supportive environment where it's OK to take risks that sometimes pay off, but sometimes don't.

Some things I did well:

  • Clearly stated the problem
  • Good engaging activity
  • Slides not too dense.
  • Casual and relaxed casual tone
  • Tested understanding
  • Good summary

However there were some things I could have done better.

  • I spent a lot of time too-ing and frow-ing from the screen to the computer. I might benefit from a Bluetooth clicker if I want to move around.
  • I used my hands a lot. I don’t know if that’s a good thing or a bad thing. I think a bit of excitement is a good thing, but some students might find all that hand waving distracting
  • I surprised that one of the comments I got in my feedback was that I was favouring one side of the classroom more than the other.  I was not aware of that but it is very obvious from the video. I have since caught myself doing that in many of my other classes.

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