When planning to teach (or study) individual topics in the new IB Psychology course, you might find yourself faced with the question: do I go for depth or breadth?  For example, should you teach (or learn) three effects of hormones on behaviour, or just one?

The new course has supposedly been designed to allow the choice of either approach. However,  in this post I’m going to put forward five reasons why I think you should aim for depth over breadth. If you keep reading to the end, you’ll also see why this advice is a little bit hypocritical on my behalf.

Depth refers to studying a topic by looking at one example with one thorough explanation and supporting research, whereas breadth refers to looking at multiple examples with one or more explanations and research (read more here).


Reason #1: Always one, never two

In the new guide where a number is stated, it’s always “one or more.” Unlike in the old syllabus that often used plurals or stated a requirement for understanding two or more examples, this is not the case with the new guide. So with the new syllabus there should never be exam questions that state a requirement for using two or more examples. In fact, one of the questions in the specimen papers was changed to reflect this, as it went from this:

To what extent do findings from two or more psychological studies related to schema theory support the understanding of memory processes?

to this:

To what extent do findings from one or more psychological studies related to schema theory support the understanding of memory processes?

So you can rest easy that you shouldn’t be caught out by only looking at one example. In fact, in the new guide (and specimen exam papers) the phrase “one or more” is often stated explicitly.

Students will always need to understand at least one example. The questions might even  allow students to use only one example. For example, they may ask a question like “Discuss one effect of neurotransmitters on human behaviour.” While this question should be written as “one or more,” I wouldn’t want to focus on breadth because you’re gambling on that “or more” phrase always appearing in an IB exam question, and that’s a gamble I’m personally not willing to take. Preparing at least one example per topic in depth protects against these types of questions in exams that specify only one example should be used.


Reason #2: SAQ Preparation

The mandatory short-answer questions (SAQs) that can come from anywhere in the course in Paper 1, Part A is why I like to ensure I’ve explored at least one topic (and relevant study) in depth. Because while it’s not set in stone, it’s a pretty safe bet that SAQs will only ask for one example or study. In fact, most topics in the biological approach in the new guide state this explicitly. For this reason, it’s essential that students can provide one core argument and explain one supporting piece of research for their argument in relation to the topic to ensure they’re prepared for any SAQ. Students need to be able to do this for all three approaches (biological, cognitive and sociocultural) so making sure that you have taught one example really well is essential.


Reason #3: Knowledge versus Understanding

The biggest reason, I think, why students achieve mainly 4s and 5s and very few get 6s and 7s in IB Psychology is because the focus is on knowledge (remembering stuff), as opposed to understanding (applying relationships to address questions). This is evidenced by the examiner’s comments every year that lament student answers are “too descriptive.”

This is especially true when it comes to using studies. For example, students can describe HM’s case study really well when asked about a study on localization, but they often miss the two or three sentences of explanation that show how his study demonstrates the function of the hippocampus in memory consolidation. To focus on more studies is, in my opinion, adding to the risk that students will be too busy focusing on comprehending the studies that they won’t have time to be able to understand how to apply them in support of specific arguments. One study described in detail and explained fully, is better than two just described, I think.


Reason #4: Critical Thinking

If students can’t apply their knowledge of a study to support a core argument, there’s no way they will be able to critically evaluate that same study. Critical thinking requires going beyond understanding and the ability to explain how things are related, and it requires thinking in the abstract about relationships. The more examples and studies that are lumped into a course, the longer it takes to first comprehend the details, then understand their applications, and finally what time is left for applying critical thinking skills is going to be really limited. This will reduce the potential marks available in essays.

By exploring topics in depth, you’ll increase the chances of being able to develop an ability to explore topics at all three levels of thinking:

  1. Knowing
  2. Understanding
  3. Abstracting (critical thinking)

Reason #5: Essays are shorter than you think

Essays in IB Psychology should be around 800 – 950 words. This is more than enough to expect of a high school student to write in one hour, by hand, in exam conditions, With this in mind, I instruct my students that a general guide for essay structure should be the following (of course the word counts outlined below are rough approximations and I don’t expect them to count – it’s just to demonstrate how little “content” is actually required in answers):

  • Introduction (100 words)
  • Central argument (150 – 200 words)
  • Supporting research (300 – 400 words)
  • Counter-argument/s (100 – 200 words)
  • Conclusion (50 words)

In a good essay, I think there’s only time to make one-well developed argument and one counter-argument. There needs to be two studies in there as well (either two to support the core argument or one each – core and counter). To describe and explain a study properly, it takes about 150 to 200 words. Do this twice, add your arguments, intro and conclusion, and you’ve got an awesome essay.

If students are trying to have three or four examples, they will find that in the time available they will have to fly over the surface to get everything in to the answer, not to mention they’ll have a lot more content to revise and prepare. This is why they’ll have answers that are too descriptive.

For example, I’d prefer students to be able to provide a thorough explanation of how individualistic and collectivist values can influence a marriage, rather than five different behaviours that are influenced by five different cultural dimensions.

Example Essay Post – Technological Techniques 


Why I’m a hypocrite

Despite my attempts here to convince you that breadth is better than depth, in my own course I include far more examples and studies than students will ever use in an exam. But this is only in some topics, not all.

This is most evident in the biological approach. For example, my students have four different ways to discuss localization of brain function, three examples of hormones and multiple ways to discuss technology.

But this is a natural by-product of combining the options with the core: students need to understand how biological variables (as well as cognitive and sociocultural ones) influence behaviours in the options, so it’s only natural that there’ll be more than one example relevant to the topics.

For example, the role of cortisol in memory is covered when we learn about emotion and memory (cognitive approach), which is a possible etiology of PTSD (abnormal psych’ option). The role of testosterone is also covered when we look at attraction and competition (topics in human relationships). These same topics can both also be applied to evolutionary explanations of behaviour.

During each unit when these topics appear, I still ensure that they’re  explored in depth, so students can reach all three levels of thinking about the related concepts and research. And now there’s an added benefit of when it comes to revision time they can choose only one example to prepare and master. Or if the question adds the phrase “or more,” weaker students who can only remember details have more to write about and so more chances of scoring marks. This is just one of the benefits I’ve found of moving away from a linear approach and moving towards a thematic one.

These are just my ideas and I welcome you to post your thoughts in the comments.