“It is not what the man of science believes that distinguishes him, but how and why he believes it. His beliefs are tentative, not dogmatic; they are based on evidence, not on authority or intuition.”

Russell, 1945

I posted my Critical Thinking in Psychology essay recently where I discuss in depth critical (or rational) thinking in the context of A Level psychology. Here I want to share one of my favourite lessons of the year where I encourage my students to start thinking critically (find the lesson powerpoint at the bottom of the post or here).

One approach to increase students critical thinking skills is to get them considering methodological issues outside of the narrow framework of each subject specification and bring these issues to life. The use of activities such as ‘More cat owners have degrees’ demonstrating the dangers of misinterpreting correlational research and the possible bias caused by funding, and ‘The dangers of bread’ again illustrating issues of inferring causation from correlation act as excellent points for discussion about causation and correlation. Articles such as these teach students to be ‘savvy consumers and producers of research’ and develop the abilities needed to analyse, synthesise and applied learned information.

A key element of critical thinking is not taking results and conclusions at face value and questioning the methods that were used and any biases that these could have introduced when making inferences from results.  I have designed several activities  to make learners aware of  ‘blind acceptance of conclusions’conclusions’ and the fallibility of accepting results  without question. I have pulled all of these activities into one lesson with the aim of engaging students and creating an enthusiasm about evaluation.

Initially, I start with abstract questions to get the learners considering critical thinking outside of psychology and allow them to develop their own awareness. This starts from the moment they enter the room when the starter is the question ‘How many uses can you think of for a paper clip‘. After giggles, head scratching and some quite lateral thinking we move on to discuss what ‘critical thinking’ is.

Before moving into discussion explicitly linked to psychology studies I ask them to write some instructions as to how to make a piece of toast. The students are a little suspicious at this point but after a few minutes you get the usual: get the bread, put in the toaster … and of course the debate on Nutella vs Marmite! Then I pose the question ‘but where did you get the toaster from …‘ and show the excellent TED video ‘Thomas Thwaites: How I built a toaster — from scratch‘

From here is time to turn my new ‘questioning‘ students back to psychology …

The first activity is based on hindsight bias, or the “I knew that all along” attitude, helping students become aware of the fact that anything can seem commonplace once explained if you are not aware of the underlying methodology.

This was the rationale for the ‘Lazarfield task’ that starts with the class being divided into two groups with each half receiving conclusions from a study (adapted from Lazarsfeld, 1949). However, unaware of this, the two groups received the opposite findings. For example group one would receive:

“Better educated soldiers suffered more adjustment problems than less educated soldiers.”

Whereas the second group would have:

“Better educated soldiers suffered fewer adjustment problems than less educated soldiers.”

Each group have to make inferences about ‘why’ the conclusions might be true. Following on from the task students were asked to “did the findings make sense?” and to feedback their reasons. Only at this point will the class be made aware that they had the opposite findings and how easily it is to justify a finding after the fact. A discussion about the fallibility of the “I knew that already” attitude follows in relation to the students that the students have completed. This allows for the learner to review conclusions made and consider alternative arguments, confounding variables and biases in generalisations made.

To then scaffold students’ analysis and evaluation skills a set of critical thinking questions to frame evaluation of research was adapted. These critical thinking questions provide students with important questions that they can use to establish the credibility of a research method. It also allows differentiation across learners providing the opportunity for those with low ability to give limited responses and the more able students to expand and demonstrate their synoptic awareness of research methods and the surrounding issues and concepts.

This is one of my favourite sessions of the year – you can actually see the students thinking, discussing and debating issues. They are staring to think like psychologists, like scientists. Not accepting what is in front of them but asking important questions. What is great to see is the reaction following the session – how the students often refer back to the session.

My only warning – I asked my students to keep asking ‘but why?‘ – they do!

How do you develop critical thinking skills in your learners? Could you adapt this session to your subject? If you do – please share it in the comments.