# 348. A-Level colouring (Updated)

Those of you who follow this blog will know I have a thing for explaining with colours. This isn’t just a gimmick for younger students, it also works for 16-18 year olds.

In the picture below we were looking at proving a statement involving reciprocal trigonometric functions and fractions. A common source of misconception with this kind of question is that students split the question into working with the numerator and denominator separately, then make mistakes when they put them back together. They can’t see the big picture.

Image credit: Mathssandpit

When I discussed this on the board I used separate colours for the expressions in the numerator and denominator. The class could follow the logic so easily. It’s probably my most successful introduction to this topic. I saw that some students used highlighter on their notes after I’d gone through it, so they could track the solution.

The second type of question we looked at was solving a trigonometric equation. The straight forward expansion was all in one colour, but the roots of the quadratic were highlighted in different colours. The reasoning behind this was that students often solve half the quadratic and neglect the other impossible solution. Our exam board likes to see students consider the other solution and formally reject it. It makes the solution complete. By using a colour, the impossible solution stands out and reminds students to provide a whole solution.

Image credit: Mathssandpit

So when you are planning for misconceptions at A-level, remember that coloured pens aren’t just for younger students.

Update: 22nd October

The brilliant Mr B has shared how he uses colour to identify the forces in perpendicular directions in Mechanics.

# 58. Free Revision App

I’ve recently started using the Edexcel Past Papers revision app (Apple & Android compatible) with my GCSE and A-Level classes.

It is basically a database of past papers for all Edexcel subjects and qualifications, even iGCSE. You search by qualification, then subject, then exam session, then paper. The papers and mark schemes are already available on the internet, but the app is much quicker than googling them. It is not a complete revision resource, but it is fairly comprehensive app. Some of the PDFs are e-versions, some are scans. You can also share papers by email, which allows you to print.

The recent material is still only available through the secure teacher area of the Edexcel website, so your mock exams won’t be compromised.

My Y11 have downloaded it for personal use when they are on study leave. They suggested that even though they don’t use Edexcel for every subject, they could use it as a source of extra questions when they run out of revision materials. I’m actually impressed that they intend doing so much revision!

My Y12 have used this app in class for checking their work and also when they have forgotten the exam paper I have copied for them. It also saves me having to print out new papers and dashing to the printer. I find it rather handy having a selection of mark schemes in my pocket, especially when students are working on a variety of papers.

Note: This app has mixed reviews on both itunes and the Google Play store. I think it depends what your expectations are and what device you have.