These squares have been made from Cuisenaire rods. Can you describe the pattern? What would the next square look like?

Compare the numbers of particular tiles in one or all of these three designs, inspired by the floor tiles of a church in Cambridge.

In each of the pictures the invitation is for you to: Count what you see. Identify how you think the pattern would continue.

Can you continue this pattern of triangles and begin to predict how many sticks are used for each new "layer"?

Surprise your friends with this magic square trick.

Polygonal numbers are those that are arranged in shapes as they enlarge. Explore the polygonal numbers drawn here.

While we were sorting some papers we found 3 strange sheets which seemed to come from small books but there were page numbers at the foot of each page. Did the pages come from the same book?

Take a counter and surround it by a ring of other counters that MUST touch two others. How many are needed?

Can you dissect an equilateral triangle into 6 smaller ones? What number of smaller equilateral triangles is it NOT possible to dissect a larger equilateral triangle into?

Can you make dice stairs using the rules stated? How do you know you have all the possible stairs?

This challenge encourages you to explore dividing a three-digit number by a single-digit number.

Think of a number, square it and subtract your starting number. Is the number you’re left with odd or even? How do the images help to explain this?

One block is needed to make an up-and-down staircase, with one step up and one step down. How many blocks would be needed to build an up-and-down staircase with 5 steps up and 5 steps down?

How can you arrange these 10 matches in four piles so that when you move one match from three of the piles into the fourth, you end up with the same arrangement?

This challenge, written for the Young Mathematicians' Award, invites you to explore 'centred squares'.

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?

What happens if you join every second point on this circle? How about every third point? Try with different steps and see if you can predict what will happen.

Watch this animation. What do you notice? What happens when you try more or fewer cubes in a bundle?

Here are some arrangements of circles. How many circles would I need to make the next size up for each? Can you create your own arrangement and investigate the number of circles it needs?

In how many different ways can you break up a stick of 7 interlocking cubes? Now try with a stick of 8 cubes and a stick of 6 cubes.

A game for 2 players. Set out 16 counters in rows of 1,3,5 and 7. Players take turns to remove any number of counters from a row. The player left with the last counter looses.

Does this 'trick' for calculating multiples of 11 always work? Why or why not?

Find the sum and difference between a pair of two-digit numbers. Now find the sum and difference between the sum and difference! What happens?

This challenge focuses on finding the sum and difference of pairs of two-digit numbers.

Sweets are given out to party-goers in a particular way. Investigate the total number of sweets received by people sitting in different positions.

What happens when you round these three-digit numbers to the nearest 100?

In this game for two players, the idea is to take it in turns to choose 1, 3, 5 or 7. The winner is the first to make the total 37.

What can you say about these shapes? This problem challenges you to create shapes with different areas and perimeters.

Tom and Ben visited Numberland. Use the maps to work out the number of points each of their routes scores.

Ben’s class were cutting up number tracks. First they cut them into twos and added up the numbers on each piece. What patterns could they see?

Here are two kinds of spirals for you to explore. What do you notice?

An article for teachers and pupils that encourages you to look at the mathematical properties of similar games.

How many ways can you find to do up all four buttons on my coat? How about if I had five buttons? Six ...?

This challenge asks you to imagine a snake coiling on itself.

We can arrange dots in a similar way to the 5 on a dice and they usually sit quite well into a rectangular shape. How many altogether in this 3 by 5? What happens for other sizes?

It starts quite simple but great opportunities for number discoveries and patterns!

Charlie has made a Magic V. Can you use his example to make some more? And how about Magic Ls, Ns and Ws?

Only one side of a two-slice toaster is working. What is the quickest way to toast both sides of three slices of bread?

Try out this number trick. What happens with different starting numbers? What do you notice?

An investigation that gives you the opportunity to make and justify predictions.

In this problem we are looking at sets of parallel sticks that cross each other. What is the least number of crossings you can make? And the greatest?

Use the interactivity to investigate what kinds of triangles can be drawn on peg boards with different numbers of pegs.

Watch this video to see how to roll the dice. Now it's your turn! What do you notice about the dice numbers you have recorded?

Can you find a way of counting the spheres in these arrangements?

This task encourages you to investigate the number of edging pieces and panes in different sized windows.

Are these statements always true, sometimes true or never true?

Put the numbers 1, 2, 3, 4, 5, 6 into the squares so that the numbers on each circle add up to the same amount. Can you find the rule for giving another set of six numbers?

This article for primary teachers discusses how we can help learners generalise and prove, using NRICH tasks as examples.

Find a route from the outside to the inside of this square, stepping on as many tiles as possible.

Watch this film carefully. Can you find a general rule for explaining when the dot will be this same distance from the horizontal axis?