This collection of resources encourages you to be playful with numbers.
There are games that require you to think strategically, problems that challenge you to make conjectures and work systematically, and articles that offer insights into the structure of number.
Got It
Age 7 to 14
Challenge Level
A game for two people, or play online. Given a target number, say 23, and a range of numbers to choose from, say 1-4, players take it in turns to add to the running total to hit their target.
Summing Consecutive Numbers
Age 11 to 14
Challenge Level
15 = 7 + 8 and 10 = 1 + 2 + 3 + 4. Can you say which numbers can be expressed as the sum of two or more consecutive integers?
Missing Multipliers
Age 7 to 14
Challenge Level
What is the smallest number of answers you need to reveal in order to work out the missing headers?
Factors and Multiples Game
Age 7 to 16
Challenge Level
A game in which players take it in turns to choose a number. Can you block your opponent?
Product Sudoku
Age 11 to 16
Challenge Level
The clues for this Sudoku are the product of the numbers in adjacent squares.
American Billions
Age 11 to 14
Challenge Level
Play the divisibility game to create numbers in which the first two digits make a number divisible by 2, the first three digits make a number divisible by 3...
Generating Triples
Age 14 to 16
Challenge Level
Sets of integers like 3, 4, 5 are called Pythagorean Triples, because they could be the lengths of the sides of a right-angled triangle. Can you find any more?
Divisibility Tests
Age 11 to 16
This article explains various divisibility rules and why they work. An article to read with pencil and paper handy.
NRICH is part of the family of activities in the Millennium Mathematics Project.