Dozens
Age 7 to 14 Challenge Level:
Do you know a quick way to check if a number is a multiple of two? How about three, four or six?
Cops and Robbers
Age 7 to 16 Challenge Level:
Can you find a reliable strategy for choosing coordinates that will locate the robber in the minimum number of guesses?
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?
Dicey Operations
Age 11 to 14 Challenge Level:
Who said that adding, subtracting, multiplying and dividing couldn't be fun?
Have You Got It?
Age 11 to 14 Challenge Level:
Can you explain the strategy for winning this game with any target?
Diamond Collector
Age 11 to 14 Challenge Level:
Collect as many diamonds as you can by drawing three straight lines.
River Crossing
Age 11 to 14 Challenge Level:
There is nothing half so much worth doing as simply messing about in boats...
Gabriel's Problem
Age 11 to 14 Challenge Level:
Gabriel multiplied together some numbers and then erased them. Can you figure out where each number was?
Product Sudoku
Age 11 to 14 Challenge Level:
The clues for this Sudoku are the product of the numbers in adjacent squares.
Wipeout
Age 11 to 14 Challenge Level:
Can you do a little mathematical detective work to figure out which number has been wiped out?
Crossing the Bridge
Age 11 to 14 Challenge Level:
Four friends must cross a bridge. How can they all cross it in just 17 minutes?
Square It
Age 11 to 16 Challenge Level:
Players take it in turns to choose a dot on the grid. The winner is the first to have four dots that can be joined to form a square.
11x11 Square
Age 11 to 16 Challenge Level:
Here's a neat trick you can do with an 11 by 11 square...
Warmsnug Double Glazing
Age 14 to 16 Challenge Level:
How have "Warmsnug" arrived at the prices shown on their windows? Which window has been given an incorrect price?
Latin Numbers
Age 14 to 16 Challenge Level:
Can you create a Latin Square from multiples of a six digit number?
NRICH is part of the family of activities in the Millennium Mathematics Project.