If every teacher and every paper in a multi-disciplinary course uses their own conception of critical thinking, students end up more confused than critical. So how do you build a shared understanding of critical thinking in a multi-disciplinary course?

Go concrete: Find agreement about what a critical thinker does. For example, they give reasons and explanations, they uncover and question assumptions, etc. It will be virtually impossible to get agreement if your discussion remains solely in the abstract realm of terms like ‘critical thinking’ and ‘reflection’. Instead look at what thinkers do – their thinking moves or thinking behaviours.

Agree on a developmental core: Find agreement about the developmental core for students learning to be critical thinkers, rather than trying to find agreement about the final, expert version of critical thinking. The critical thinking of a scientist is different from the critical thinking of a health professional. But the path to learn these expert kinds of critical thinking is similar, and there are developmental stages that all students need to go through. Find agreement on the critical thinking needed for a first year student, which will be the basis for eventually learning to be a doctor or an anatomist, or a physicist, etc.

A doctor has to judge likely diagnoses based on what they observe, and what they know about potential conditions. A scientist has to evaluate the evidence from multiple studies in order to make an informed conclusion. However, at the start of the developmental process, a six year old critical thinker merely has to learn to use the word ‘because’ appropriately in a sentence. A first year student at University is at a developmental stage between these two extremes. What is the developmental core of critical thinking that builds on using ‘because’, and which can equally lead to thinking like a doctor or thinking like a scientist?

For example, perhaps first year critical thinkers need to explain, justify and apply. Firstly they have to explain and justify their answers (rather than merely repeating the answer they memorised), and secondly, they need to apply what they learn in lectures so they can solve problems. If they learn these two aspects of critical thinking in their first year, they have the foundations for later learning the more specialised versions of critical thinking.

Stick to a small developmental core: If you stick to what critical thinkers do, and the developmental core of critical thinking, you are likely to find agreement about critical thinking even in a multi-disciplinary course. However, don’t try to include all aspects of expert critical thinking, but only the developmental core.

Having a few core thinking moves or thinking behaviours like justifying or applying is more useful than trying to include everything. Learning to be a critical thinker is like learning to be a great pianist. They both require lots and lots of practise doing ‘scales’ where students are asked, again and again and again, to explain, justify and apply. For example, for every answer you give, you might ask them “why is that the correct answer?” By regularly and frequently engaging in this thinking, students internalise it until it becomes second nature to them and they are critical thinkers. They will learn more by repeating this simply prompt than they will by frequently adding in new prompts and new aspects of thinking.

Assess critical thinking moves and behaviours: You can assess their thinking based on whether they do the core thinking. Do they give reasons or not? Do they apply their knowledge to solve novel problems?

Design assessment tasks that cannot be completed except by using the critical thinking moves. Students should be unable to give an answer by remembering the lecture or the text-book, or by googling. Tasks that involve evaluating and applying are useful for this purpose.

When you assess make sure you distinguish between assessing whether they have said the right thing (you agree with them) and whether they have done the thinking (they have given reasons to justify their answer). Just like assessing mathematics, you need to assess whether they have the right answer independently of whether they have demonstrated their working or their thinking. For example, they might have the right answer but have not given any reasons or explanations to back this up. Alternatively they could have the wrong answer but demonstrated excellent explanation and justification based on a false premise. The second example shows good critical thinking, but the first one does not, yet we are likely to only reward the first answer. When assessing critical thinking we have to put aside whether we agree or disagree with their answer and instead look for the thinking. For example, if they give us the wrong answer, we ask them “Why do you think that is correct?” and if they give us the right answer, we ask them “Why do you think that is correct?”