Every year, the University of Southampton runs the Cipher Challenge – a series of coded messages that you have to try and solve each week, with an overarching plot and a community of code crackers included. At the school’s Cipher Club, we learn about these ciphers as we solve them, using different challenges and websites to help us accomplish this. We meet every Thursday, and, under the pleasing name of Code Crackers and Cheese, try and solve the ciphers that have been set (with a lot of help from Mr Amblin!). While there is a competitive aspect during the time of the Cipher Challenge, mostly we just try to have fun and to learn new things. The club is a place where we can all meet up to discuss new ciphers and how they work.

We’ve learnt about many different types of ciphers: substitution ciphers, rail fence ciphers and vigenère ciphers to name a few. All of us have worked really hard to understand them and how we can use them to crack coded messages, especially during the Challenge. For example, the vigenère cipher featured prominently in the Cipher Challenge, and we learnt all about it. To solve it, we discovered, you need to have a keyword, line it up with the plaintext, and use each lined up pair of letters as coordinates in a grid employing different degrees of Caesar shifts. As the challenges go on, more are learnt and they get easier, until the last few ones where no website or page online can help you, and you need to utilise all that you have been taught. 

The Cipher Challenge and Cipher Club has been an amazing experience and we’ve learnt so many new things. It’s fun, but still stretches us enough so we learn something new every week and go home feeling accomplished and proud. The club has been really enjoyable because we all work together, help each other and have fun cracking codes while learning about new ciphers. The short period of time we use to learn about this (the club usually goes on for around 20 minutes) is a perfect way of giving us independence to do private research and find out about ciphers on our own. Although it’s fun even when you’re not competing, we’re all really looking forward to next October when the live Cipher Challenge will start again. We feel better prepared this time and know more about what to expect, but there will still be plenty of learning opportunities. 

Matilda, Julia and Luna