Computing at School (CAS) and Diagnostic Questions, in partnership with others (including OCR, Edexcel, Microsoft, Google, ARM), have developed a bank of diagnostic questions to support the computing curriculum across Key Stages 3 to 4, that will:

The entire collection covering both KS3 and KS4 is available to schools and students, for free, forever. You’ll find everything you need to know about Diagnostic Questions and the Computing quizzes and questions in this guide!

Looking for computing content on Eedi?

We have now moved all computing content to Diagnostic Questions. To access all the quizzes below, ensure you are logged into Diagnostic Questions before clicking on the links.

Please note: All of our computing content is housed on our Diagnostic Questions website. If you assign a quiz to students via Diagnostic Questions your students must log into their accounts on Diagnostic Questions to access it. You must be logged in to DQ before clicking on the links.

Every question on Diagnostic Questions is a multiple choice, quality assured computing diagnostic question created by our partners.

We have curated several large sets of quizzes (made up of 5-20 questions) to save you the work of choosing questions. Content we have available is:

You can find this content on our Diagnostic Questions Collection page.

If you need any help, drop us an email - [email protected]

The focus of the Computing collection on DQ is squarely on formative assessment: using low-stakes quizzes to improve the quality of teaching and learning:

With such individualised information, students achieve a deeper understanding of their own strengths and weaknesses and feel more confident in their learning.

All the questions in DQ are multiple-choice questions (MCQ). Many people think that MCQs are second-best, useful only because they are easily marked. But the research says the opposite: in fact, high-quality MCQs are extremely effective at promoting learning.

The “high quality” bit is important! As part of our partnership, Eedi and Microsoft Research are also developing ways of learning, from anonymised data on hundreds of millions of answers to tens of thousands of questions, which questions “work well”, how hard they are, and which is most suitable for a particular student or class. Here’s an early video about this work.

We're going to look at an innocent-looking question about the bubble sort algorithm. What could possibly go wrong?

What do you think the most popular wrong answer is, and why might a student select it?

And here are the results (with almost 5000 people attempting this question!)

So, less than 30% of students get this question correct.

Okay, so why do students get this question wrong? Well, let’s dive into some student explanations to try to find out.

For each incorrect answer, the author writes an explanation so we can compare these with the explanations students give.

​Answer A

Author explanation: The students think it is one pass per number of items

Student explanation: "because thats how many numbers there are"

Answer B

Author explanation: The student assumes the algorithm knows the list is sorted

Student explanation: "the list is already in order, there is no need to sort the list, its already in ascending order from low to high."
​
​Answer D

Author explanation: The student thinks it is the number of items - 1

Student explanation: "because after three numbers have been checked youd know for sure that it is in the correct order"

Let's not forget the correct answer and the real student explanation for the correct answer:

Answer D from a student: "Because its already sorted so it just needs to check that the order is correct which it is"