When to ask a Diagnostic Question — part 3
In this series of posts concerning the pedagogy and practicalities of using diagnostic questions, we have considered:
What is a Diagnostic Question?
What makes a good Diagnostic Question?
Asking Diagnostic Questions in class
Responding to Diagnostic Questions in class
When to ask a Diagnostic Question — Part 1
When to ask a Diagnostic Question — Part 2
In the last two posts, we have seen four reasons why asking a diagnostic question or two at the start of each lesson may be a really beneficial thing to do for both you and your students — and indeed it is now part of my regular routine. In this post, we consider why you might want to ask a Diagnostic Question at other points in your lesson.
Middle of the lesson
Imagine you are halfway through a particular lesson. The students are working on some carefully prepared sequence of questions or activity . They are all at different points, working at their own pace. You are trying to make an informed decision whether or not now is the right time to move onto the next part of the lesson, maybe to introduce the next skill or concept. One of the best ways to do this is to ask a well-designed diagnostic question.
William (2011) describes diagnostic questions used in this ways as hinge questions (Fun fact: see what happens if you visit hingequestions.com). He explains:
the central idea here is that the teacher designs each lesson with at least one “hinge” in the instructional sequence. The hinge is a point at which the teacher checks whether the class is ready to move on through the use of a diagnostic question. How the lesson proceeds depends on the level of understanding shown by the students, so the direction of the lesson hinges at this point.
Diagnostic questions presented in the way in this series of posts are perfect for this as they are quick to ask, quick to get data back from, and do not simply tell you where certain students are going wrong, but why they are going wrong. This allows you to intervene where needed.
So, during a lesson on using graphs to solve equations, I may ask the students to stop what they are doing, ask a diagnostic like the one below in the manner described in an earlier post:
If there are any students struggling, I can go and help them — armed with the knowledge of exactly why they are struggling based on the answers they have given — whilst the rest of the class crack on.
Conversely, if everyone gets the question right, then onward and upwards!
End of the lesson
I no longer end my lessons on a difficult question. For me, a key purpose of the end of the lesson is to inform the starting point of the next lesson. I want to get a quick and accurate sense of my students’ understanding of what I have taught them that particular lesson so I know my starting point the next time I see them. Hence, I use a diagnostic question.
Of course, we need to bear in mind that the distinction between learning and performance warns us against inferring that students have definitely learned everything when we assess them immediately after instruction. However, wrong answers certainly tell us there are problems we need to address, and the specific nature of those problems. Likewise, if everyone gets the last question correct (and it is a good one!), then I have evidence to move on next lesson, but crucially making a note to revisit the concept at numerous points in the future.
A common practice among teachers is to issue an Exit Ticket at the end of the lesson. This is essentially a question that students complete in the final minutes of the lesson and hand to the teacher on the way out. The teacher then has a quick look over the students’ responses and uses this to inform their planning. Diagnostic questions are perfect for this purpose. They are lightening fast, both for the students to complete and for the teacher to mark. I have started printing them out and adding a section for the student to explain their answer. This enables me to glance at their choice of A, B ,C and D, and then dig deeper into the reason behind this choice if I need to. It also allows the students to reap the benefits from self-explaining. An exit ticket might look like this:
Finally, the end of the lesson is also an opportunity to give students a question based on what they will be studying next lesson. This serves a dual purpose — it allows me to get a sense of their understanding of key concepts so I can adjust my planning accordingly, and it also provides an opportunity to take advantage of the Pretest Effect outlined in the previous post.
Homework
As we have seen, writing a good diagnostic questions is flipping hard… which makes them the ideal activity to give to your students! Students must demonstrate a sound understanding of the key concept or skill, together with an appreciation of where other students may go wrong.
A homework following a lesson on upper and lower bounds may look like this:
- Write a diagnostic question on upper and lower bounds
- Write a model explanation for the correct answer
- Write a sentence explaining your choices for each incorrect answer
Here is a homework from one of my students — let’s call her Josie… because that is in fact her name — on bounds:
The same homework can be set to all students, giving each the opportunity to demonstrate the depth of their knowledge of a concept. Such a homework also has the advantages of being relatively quick for me to mark, illuminating in terms of the insights I can learn, and may provide me with a new batch of diagnostic questions that I can use with my students. Everyone’s a winner.
And if this has whetted your appetite for more diagnostic questions, well then there are more than 40,000 of them (including 30,000 for maths), all freely available at diagnosticquestions.com
Subtle advertisement alert: my book How I wish I’d taught maths, which contains an entire chapter dedicated to the practicalities, benefits and considerations when using diagnostic questions in the classroom, is available to buy from Amazon and John Catt Education Ltd.
References
- Wiliam, Dylan. Embedded formative assessment. Solution Tree Press, 2011.
