This half term I’m trying something new with my year 6 kids. For the last few years I’ve looked at networks and how computers work and they’ve enjoyed it. However this year I’m adding some cryptography into the mix too. Cryptography, while hard to spell, has the potential to really enrich the maths and problem solving skills they use in the classroom every day. The intrigue and adventure when solving problems is something we all know kids love, and really gets them engaged with their learning.
Everywhere I’ve looked has cryptography activities for secondary, but I couldn’t find any for primary. So I decided to look at some myself, and adapt for my primary kids! Over the next few weeks I’m going to be looking at different codes and ciphers to try and give the pupils different challenges. Below I’ve laid out the ones I will be using, as well as presentations and activity packs to go with it.
The Caesar cipher, also known as a shift cipher, is one of the simplest forms of encryption. It is a substitution cipher where each letter in the original message is replaced with a letter corresponding to a certain number of letters up or down in the alphabet. This one is a great activity for the kids to make, and then keep for future challenges.
The pigpen is a geometric shape cipher, which exchanges letters for symbols which are fragments of a grid. The user needs to have the guide to be able to work out the messages. There are also other variants of the pigpen cipher which are great to explore.
The Braille system is used by blind people to read and write. The Braille system uses a set of raised bumps or dots that can be felt with a finger. In this case the language is printed as dots on the page for pupils to interpret. Each set of dots is a character in an alphabet, and the numbers and some punctuation.
The NATO phonetic alphabet is a way of using words to replace letters. The first letter of the word is the letter the word stands for. It is used to clearly say letters out loud when they might be hard to hear such as over the phone or when people are talking from different countries, or when it is important to be accurate such as in the military and in air travel.
Hope you found this useful and it inspires some pupils to get into code breaking and cryptography!