Unexpected Ordering
Age 5 to 7 Challenge Level:
Watch the video of Fran re-ordering these number cards. What do you notice? Try it for yourself. What happens?
Next-door Numbers
Age 5 to 7 Challenge Level:
Florence, Ethan and Alma have each added together two 'next-door' numbers. What is the same about their answers?
Eightness of Eight
Age 5 to 7 Challenge Level:
What do you see as you watch this video? Can you create a similar video for the number 12?
Ring a Ring of Numbers
Age 5 to 7 Challenge Level:
Choose four of the numbers from 1 to 9 to put in the squares so that the differences between joined squares are odd.
Strike it Out
Age 5 to 11 Challenge Level:
Use your addition and subtraction skills, combined with some strategic thinking, to beat your partner at this game.
Dotty Six
Age 5 to 11 Challenge Level:
Dotty Six is a simple dice game that you can adapt in many ways.
I'm Eight
Age 5 to 11 Challenge Level:
Find a great variety of ways of asking questions which make 8.
Digit Addition
Age 5 to 11 Challenge Level:
Try out this number trick. What happens with different starting numbers? What do you notice?
Seeing Squares
Age 5 to 11 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.
School Fair Necklaces
Age 5 to 11 Challenge Level:
How many possible necklaces can you find? And how do you know you've found them all?
Surprising Split
Age 7 to 11 Challenge Level:
Does this 'trick' for calculating multiples of 11 always work? Why or why not?
Number Differences
Age 7 to 11 Challenge Level:
Place the numbers from 1 to 9 in the squares below so that the difference between joined squares is odd. How many different ways can you do this?
Magic Vs
Age 7 to 11 Challenge Level:
Can you put the numbers 1-5 in the V shape so that both 'arms' have the same total?
Consecutive Numbers
Age 7 to 14 Challenge Level:
An investigation involving adding and subtracting sets of consecutive numbers. Lots to find out, lots to explore.
Subtraction Surprise
Age 7 to 14 Challenge Level:
Try out some calculations. Are you surprised by the results?
NRICH is part of the family of activities in the Millennium Mathematics Project.