Week 10: Code breaking – half term activity

Codes are used to send secret messages – if only you and the person who needs the information know the key to crack the code your secret will be safe!  We were going to make code wheels at the museum during half term as one of our activities to commemorate the 75^th anniversary of VE Day. Coded messages were very important during the Second World War to keep information safe from the enemy.  See if you can find out about the work of the code breakers at Bletchley Park who intercepted the German Enigma machine and managed to crack the German codes.

Code wheels are a simple way of making secret messages.  Use the wheel to write your message out, working out which letter to use in place of the one in each word.  If the person receiving the message has the same code wheel, they will be able to work out what it says.

Print the Code Wheel Scanned template on paper or card.  Cut both circles out, not forgetting the little notches in the top part to show the letters.  Make a small hole through the middle of each circle – a pencil will be fine for this.  Attach the two circles together with a split pin if you have one, but if not just push some string through and tie a knot to hold the two bits together.

To crack the codes just move the top circle around so the code letter appears in the gap at the bottom – whichever letter then appears in the gap at the top is the real one that will help spell out the secret word.

See if you can crack the coded message below with your code wheel.

R W W D T X   L H E R V N   I D V N E D B N   Q Y V R Y Q

Now you can have a go at making your own messages, and see if you can think of other ways of making your code even harder to crack!