Colour Blindness in the classroom – 5 ways to help learners with CVD

Colour Blindness in the classroom – 5 ways to help learners with CVD

Colour can be a useful tool in the classroom, providing contrast in diagrams, graphs and charts or adding interest and vibrancy to teaching materials. But for some learners, it can also be an obstacle. Carly Hill-Banks, WJEC Editorial & Accessibility Advisor explains:

Colour vision deficiency (CVD), more commonly known as colour blindness, affects 1 in 12 boys (8%) and 1 in 200 girls (0.5%). In the UK there are approximately 450,000 colour blind school age pupils. Statistically speaking, this means at least one child in every classroom will have some degree of colour blindness.

 

 

How CVD affects learners

Due to a combination of factors, including a lack of awareness and the absence of routine screening, most remain undiagnosed throughout their school career. This can put learners with CVD at a disadvantage when exams or classroom activities rely on colour.

Some subject areas are especially difficult for affected learners, such as Geography. Erin Roberts, Subject Officer for AS/A Level Geography at WJEC explains:

“With a range of photographs, graphs, maps and diagrams to interpret, learners with colour vision deficiency may find geography lessons particularly challenging. Colour is often the primary element used to differentiate between different features and datasets.”

 

Left: Normal colour vision. Right: CVD simulation


While Geography offers some obvious examples of the issues colour blindness can cause students, there are potential pitfalls across all subject areas. This quote from Josh, a young learner with CVD, highlights the difficulties he faced in maths lessons:

“A lot of my coursework relied on colours for graphs, which I found difficult and I’d be worried about exam papers with coloured sections. When exam papers are black and white I don’t have problems understanding information. My current maths teacher uses information in PowerPoint where the background and the text are too similar, so I have to rely on my friends to tell me what they say.”


Improving CVD accessibility

At WJEC/Eduqas, we’ve long been at the forefront of creating accessible assessment materials for learners affected with CVD. In 2020 we worked closely with Colour Blind Awareness to create a comprehensive guide to developing assessment materials, and since then a CVD working group spanning all major exam boards has been established to share expertise and resources.

The lessons we’ve learned around CVD-friendly content aren’t just useful in creating exam papers – they’re equally applicable to teachers creating their own content for the classroom. Here are some ideas on how you can make your teaching materials more accessible, illustrated with examples from Geography, a subject area that can be especially challenging for learners with CVD:

 


Our tips for creating CVD-inclusive teaching materials


1. Avoid conveying information using colour alone

Good practice example of using multiple methods alongside colour to convey information in a line graph.


CVD makes differences in colour difficult to spot, which can completely obscure the meaning of an image or diagram. Wherever possible include a secondary indicator to highlight key information as well as, or instead of colour. This could include patterns, texture, labelling, underlining, bold or different font sizes. If you need to include a key, make sure it’s legibly sized and clearly matches your chosen indicators.


2. Check your materials in greyscale

Left: Normal colour vision. Right: CVD simulation


Print out your existing teaching handouts and slides in greyscale/black and white and see if you can still understand them. Better still, ask someone who’s never seen them before if they can make sense of them without colour. If not, look at using some of the indicators above to add clarity.

For future materials, consider designing without colour first, then add it later (if it’s needed!) once the meaning is already clear.


3. Don’t make assumptions

Left: Normal colour vision. Right: CVD simulation


It’s easy to assume that everyone can tell the difference between two dramatically different colours, but this is not always the case. For example, a bright red line on a map can seem obvious to someone without CVD, but be virtually invisible to people with some types of colour blindness.

The idea that colour blindness is restricted to reds and greens is also a common misconception, when in reality there are many variations on how people with CVD perceive colour.


4. Be mindful of contrast

Left: Normal colour vision. Right: CVD simulation


Always ensure that text and any labelling stands out from the background – this is important for accessibility on all levels, but particularly for learners with CVD. Pastels and shades of grey can be particularly challenging to decipher. Black on white or white on black will always offer the highest possible contrast. Photographs can also present problems, as in the above example.


5. Use the tools and information available

There are plenty of useful free tools and sources of information online that can help you better understand CVD, and how to design teaching materials to be as accessible as possible: