How to use Diagnostic Assessment to Boost KS2 Maths Progress

How to use Diagnostic Assessment Effectively in KS2

It’s individualised learning that takes on board where children are at in their learning at school – plus it builds confidence. The children love it!

Angie Bailey, Deputy Headteacher, Giles Brook Primary

What is diagnostic assessment?

Diagnostic assessment is a type of assessment that identifies an individual pupil’s level of understanding of a topic. Rather than simply testing what a pupil knows and giving them a particular score or grade, diagnostic assessments give an indication of what a pupil does and doesn’t yet not know. They help pinpoint their strengths and weaknesses and, importantly, where they have gaps in their knowledge. 

The results can then be used to inform lesson and curriculum planning to ensure gaps are plugged and misconceptions are addressed.

Why is it so important in maths?

Improving confidence and making accelerated progress in maths doesn’t just happen. It requires specific, targeted learning journeys for each and every pupil.

The successful use of diagnostic assessment can help you to regularly track where each pupil is performing, and where they need more work.

When used correctly this can help tailor and differentiate teaching provision so that pupils get help where they need most – ensuring that no pupil is left behind.

How to use diagnostic assessment effectively

In our experience, there are a few things schools can do to ensure they’re using Diagnostic Assessment effectively, and that it is enhancing their teaching rather than taking time away from it:

  • We believe good diagnostic assessments always optimise the insight per question asked. In other words, don’t overdo it. Look to maximise the impact of answers, while minimising how many questions you ask
  • Diagnostic assessment should only be used to orientate what you teach and how you teach it, it should not become overly time-consuming and should never eat into learning time. You can diagnose a pupil perfectly, but it is useless if it does not leave ample time to address any gaps that are found
  • Diagnostic assessment shouldn’t take too long! In our online intervention programmes we take about 25 minutes at the start of every term to run our initial diagnostic test and then have brief weekly assessments that last around 3-4 minutes
  • We suggest schools undertake a primary Maths diagnostic assessment roughly once a term. This means you can avoid repeated teaching throughout the year

How Third Space Learning uses Diagnostic Assessment in its 1-to-1 intervention programmes

Schools using our online 1-to-1 intervention programmes sign their target pupils up for one hour per week with their own personal online maths tutor. In that hour, we have to know what progress each pupil has made in order to determine what is taught in the following week, and to make sure that all our schools have total insight into how their money is being spent, and for what impact.

We use diagnostic assessment to pinpoint misconceptions, cement foundation knowledge, and create a tailored learning journey for the pupil to work through with a tutor.

  1. First up, we assess pupils at the start of their term with us to establish baseline knowledge and individual gaps for each pupil. This has two main purposes; to inform the teaching and, together with a post-session assessment, it helps to measure the impact of lessons on pupils.
  2. The pupils’ answers then feed into a unique algorithm which helps identify the particular lessons (and order) that will work best to boost maths progress in each individual pupil.
  3. We also conduct a mini-assessment at the end of each 1-to-1 lesson to indicate how much the pupil has progressed within that topic.
  4. Finally, we do an end of term assessment that maps onto the initial diagnostic assessment. This demonstrates the overall progress gained by that pupil in each topic.

By using diagnostic assessment in this way, we can ensure that all dedicated session time is used to target areas of weakness for our pupils, rather than teaching them what they already know or focusing on generic topics or concepts that are ‘likely’ to be an issue.

Four key principles for using diagnostic assessment in KS2

  1. Assess early

Starting early in the school year helps track real progress, as it provides a comparative baseline assessment based on a pupil’s position as they’ve returned to school after the long summer holidays. 

Each pupil chosen to receive our weekly online 1-to-1 maths lessons sits an initial assessment – called ‘Mission Zero’ – at the start of each term with us. This ensures that we’re always starting from the correct point and teaching to their current gaps.

2. Use distractors to identify common misconceptions

When you conduct your own diagnostic assessment at school, make sure that any tool or questions you use include distractors so you know why a pupils has made a mistake. This can help provide more focused feedback, as you know exactly what misconception a pupil has for each topic and question. Whereas the answers to open-ended questions can be more difficult to categorise in this way.

The diagnostic assessment in our intervention programmes uses multiple choice format, and for each question we created one correct answer and three distractors. They’re not just random wrong answers but are designed to be an answer a pupil could potentially get to based on a specific misconception.

All pre- and post-topic diagnostic assessments on the Third Space Maths Hub also follow this structure, with answer sheets linking each distractor to a common misconception to help diagnose learning gaps quickly and efficiently.

3. Low stakes, frequent testing is key to great assessment

Frequent testing ensures you’re continuously diagnosing gaps and building upon knowledge learnt each week, month, term or year.

On all our intervention programmes, the initial baseline test is topped up with assessment throughout the term. This comes in the form of a couple of questions after their 1-to-1 lesson each week. Using these answers we can continuously diagnose gaps and our tutors will always use a question the pupil got wrong in the previous week to start of the next lesson.

There are also huge range of diagnostic assessments and quizzes in the Third Space Maths Hub to use as at various points throughout the year to find out how well pupils are taking on what you’re teaching them.

4. Look beyond subject knowledge

There are more things to assess than a pupils’ subject knowledge. Don’t dismiss the power of a Growth Mindset to transform a pupil’s confidence and results in KS2 Maths. We have seen time and time again that engagement and willingness can have a big impact on whether or not a pupil secures and retains any taught knowledge.

At Third Space, we don’t just look at a pupil’s pre and post score, but on mindset and confidence too. Lots of teachers tell us the 1-to-1 sessions make a big difference on pupils’ confidence, engagement and willingness to get involved in lessons so we make sure to measure this too. As well as the initial diagnostic assessment, we ask pupils to indicate how they feel about maths at the start and end of our intervention programmes.

That way, we can gain an insight into their confidence, enjoyment and effort in maths, as well as the value they put on learning. Once pupils finish their 12-14 weeks of 1-to-1 lessons with us, we ask them to respond to the same statements again to help us assess the impact the intervention has had on these soft skills, as well as their subject knowledge and maths attainment.

See it for yourself!

Want to see first-hand how our diagnostic assessments and intervention programmes work? Let us know a date and time that works for you to:

  • Find out more about our intervention programmes
  • Learn more about how we use diagnostic assessment
  • See how our online 1-to-1 tuition works
  • Explore our comprehensive resource library
  • Get a quote for your school

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