Resources tagged with: Codes and cryptography

There are 27 NRICH Mathematical resources connected to Codes and cryptography, you may find related items under Cross-curricular contexts.

Problem Primary curriculum Secondary curriculum

What's in a Name?

Here's a very elementary code that requires young children to read a table, and look for similarities and differences.

Age 5 to 7

Challenge Level

Problem Primary curriculum Secondary curriculum

What Was in the Box?

This big box adds something to any number that goes into it. If you know the numbers that come out, what addition might be going on in the box?

Age 5 to 7

Challenge Level

Problem Primary curriculum Secondary curriculum

What's Happening?

Shapes are added to other shapes. Can you see what is happening? What is the rule?

Age 5 to 7

Challenge Level

Problem Primary curriculum Secondary curriculum

Probably a Code?

Is the regularity shown in this encoded message noise or structure?

Age 16 to 18

Challenge Level

Problem Primary curriculum Secondary curriculum

Substitution Cipher

Find the frequency distribution for ordinary English, and use it to help you crack the code.

Age 11 to 14

Challenge Level

Article Primary curriculum Secondary curriculum

Cracking Codes

Jenny Murray describes how she developed her interest in making and breaking codes.

Age 5 to 11

Game Primary curriculum Secondary curriculum

James's Code Challenge

The Enigma Project's James Grime has created a video code challenge. Watch it here!

Age 7 to 18

Challenge Level

Article Primary curriculum Secondary curriculum

Building up to Coding

This article describes the underlying mathematical ideas and skills involved in the important mathematical application of coding.

Age 5 to 11

Article Primary curriculum Secondary curriculum

Keeping it Safe and Quiet

Simon Singh describes PKC, its origins, and why the science of code making and breaking is such a secret occupation.

Age 14 to 18

Problem Primary curriculum Secondary curriculum

Some Secret Codes

Can you follow the rule to decode the messages?

Age 7 to 11

Challenge Level

Problem Primary curriculum Secondary curriculum

Unlocking the Case

A case is found with a combination lock. There is one clue about the number needed to open the case. Can you find the number and open the case?

Age 7 to 11

Challenge Level

Problem Primary curriculum Secondary curriculum

Cipher Challenge Toolkit

Our toolkit removes the drudgery of codebreaking while leaving you to do the hard thinking!

Age 11 to 18

Challenge Level

Problem Primary curriculum Secondary curriculum

Substitution Transposed

Substitution and Transposition all in one! How fiendish can these codes get?

Age 11 to 16

Challenge Level

Problem Primary curriculum Secondary curriculum

Transposition Cipher

Can you work out what size grid you need to read our secret message?

Age 11 to 16

Challenge Level

Problem Primary curriculum Secondary curriculum

Secondary Cipher Challenge Part 1

Here is the start of a six-part challenge. Can you get to the end and crack the final message?

Age 11 to 16

Challenge Level

Problem Primary curriculum Secondary curriculum

Ip?

Seventh challenge cipher

Age 16 to 18

Challenge Level

Problem Primary curriculum Secondary curriculum

Jluuis or Even Asutguus?

Sixth challenge cipher

Age 16 to 18

Challenge Level

Problem Primary curriculum Secondary curriculum

Up a Semitone?

Fifth challenge cipher

Age 16 to 18

Challenge Level

Problem Primary curriculum Secondary curriculum

Semicircle

Fourth challenge cipher

Age 16 to 18

Challenge Level

Problem Primary curriculum Secondary curriculum

Vital?

Third challenge cipher

Age 16 to 18

Challenge Level

Problem Primary curriculum Secondary curriculum

A Fine Thing?

Second challenge cipher

Age 16 to 18

Challenge Level

Problem Primary curriculum Secondary curriculum

A Roman Conversion?

First cipher

Age 16 to 18

Challenge Level

Problem Primary curriculum Secondary curriculum

Secret Transmissions

How can Agent X transmit data on a faulty line and be sure that her message will get through?

Age 14 to 16

Challenge Level

Problem Primary curriculum Secondary curriculum

More Secret Transmissions

In 'Secret Transmissions', Agent X could send four-digit codes error free. Can you devise an error-correcting system for codes with more than four digits?

Age 16 to 18

Challenge Level

Problem Primary curriculum Secondary curriculum

Stage 5 Cipher Challenge

Can you crack these very difficult challenge ciphers? How might you systematise the cracking of unknown ciphers?

Age 16 to 18

Challenge Level

Problem Primary curriculum Secondary curriculum

Numbered Cars

I was looking at the number plate of a car parked outside. Using my special code S208VBJ adds to 65. Can you crack my code and use it to find out what both of these number plates add up to?

Age 7 to 11

Challenge Level

Problem Primary curriculum Secondary curriculum

The Best Card Trick?

Time for a little mathemagic! Choose any five cards from a pack and show four of them to your partner. How can they work out the fifth?

Age 11 to 16

Challenge Level