problem Number Pyramids Age 11 to 14 Challenge level Try entering different sets of numbers in the number pyramids. How does the total at the top change?
problem Odds, Evens and More Evens Age 11 to 14 Challenge level Alison, Bernard and Charlie have been exploring sequences of odd and even numbers, which raise some intriguing questions...
problem Seven Squares Age 11 to 14 Challenge level Watch these videos to see how Phoebe, Alice and Luke chose to draw 7 squares. How would they draw 100?
problem What was in the Box? Age 5 to 7 Challenge level 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?
problem Irrational arithmagons Age 16 to 18 Challenge level Can you work out the irrational numbers that belong in the circles to make the multiplication arithmagon correct?
problem Largest Even Age 5 to 11 Challenge level How would you create the largest possible two-digit even number from the digit I've given you and one of your choice?
problem What numbers can we make? Age 11 to 14 Challenge level Imagine we have four bags containing a large number of 1s, 4s, 7s and 10s. What numbers can we make?
problem Button-Up Some More Age 7 to 11 Challenge level How many ways can you find to do up all four buttons on my coat? How about if I had five buttons? Six ...?
problem Which is bigger? Age 14 to 16 Challenge level Which is bigger, n+10 or 2n+3? Can you find a good method of answering similar questions?