Let's suppose that you are going to have a magazine which has 16 pages of A5 size. Can you find some different ways to make these pages? Investigate the pattern for each if you number the pages.
I was in my car when I noticed a line of four cars on the lane next to me with number plates starting and ending with J, K, L and M. What order were they in?
Use the clues to work out which cities Mohamed, Sheng, Tanya and Bharat live in.
Can you find which shapes you need to put into the grid to make the totals at the end of each row and the bottom of each column?
A particular technique for solving Sudoku puzzles, known as "naked pair", is explained in this easy-to-read article.
Follow the clues to find the mystery number.
Make a pair of cubes that can be moved to show all the days of the month from the 1st to the 31st.
How many ways can you find to do up all four buttons on my coat? How about if I had five buttons? Six ...?
You are given the Lowest Common Multiples of sets of digits. Find the digits and then solve the Sudoku.
A Latin square of order n is an array of n symbols in which each symbol occurs exactly once in each row and exactly once in each column.
This Sudoku, based on differences. Using the one clue number can you find the solution?
Four small numbers give the clue to the contents of the four surrounding cells.
Only one side of a two-slice toaster is working. What is the quickest way to toast both sides of three slices of bread?
This challenge, written for the Young Mathematicians' Award, invites you to explore 'centred squares'.
Seven friends went to a fun fair with lots of scary rides. They decided to pair up for rides until each friend had ridden once with each of the others. What was the total number rides?
Look carefully at the numbers. What do you notice? Can you make another square using the numbers 1 to 16, that displays the same properties?
The puzzle can be solved by finding the values of the unknown digits (all indicated by asterisks) in the squares of the $9\times9$ grid.
Given the products of diagonally opposite cells - can you complete this Sudoku?
If these elves wear a different outfit every day for as many days as possible, how many days can their fun last?
This challenge is to design different step arrangements, which must go along a distance of 6 on the steps and must end up at 6 high.
Problem solving is at the heart of the NRICH site. All the problems give learners opportunities to learn, develop or use mathematical concepts and skills. Read here for more information.
Can you use your powers of logic and deduction to work out the missing information in these sporty situations?
Bellringers have a special way to write down the patterns they ring. Learn about these patterns and draw some of your own.
A merchant brings four bars of gold to a jeweller. How can the jeweller use the scales just twice to identify the lighter, fake bar?
Stuart's watch loses two minutes every hour. Adam's watch gains one minute every hour. Use the information to work out what time (the real time) they arrived at the airport.
How could you put eight beanbags in the hoops so that there are four in the blue hoop, five in the red and six in the yellow? Can you find all the ways of doing this?
Nina must cook some pasta for 15 minutes but she only has a 7-minute sand-timer and an 11-minute sand-timer. How can she use these timers to measure exactly 15 minutes?
George and Jim want to buy a chocolate bar. George needs 2p more and Jim need 50p more to buy it. How much is the chocolate bar?
This magic square has operations written in it, to make it into a maze. Start wherever you like, go through every cell and go out a total of 15!
Can you put plus signs in so this is true? 1 2 3 4 5 6 7 8 9 = 99 How many ways can you do it?
Use the clues to find out who's who in the family, to fill in the family tree and to find out which of the family members are mathematicians and which are not.
Use your logical-thinking skills to deduce how much Dan's crisps and ice-cream cost altogether.
Explore this how this program produces the sequences it does. What are you controlling when you change the values of the variables?
Can you help the children find the two triangles which have the lengths of two sides numerically equal to their areas?
A cinema has 100 seats. Show how it is possible to sell exactly 100 tickets and take exactly £100 if the prices are £10 for adults, 50p for pensioners and 10p for children.
Place the numbers 1 to 8 in the circles so that no consecutive numbers are joined by a line.
60 pieces and a challenge. What can you make and how many of the pieces can you use creating skeleton polyhedra?
Place eight queens on an chessboard (an 8 by 8 grid) so that none can capture any of the others.
A Sudoku with a twist.
A Sudoku with clues as ratios.
Investigate the different ways you could split up these rooms so that you have double the number.
Arrange eight of the numbers between 1 and 9 in the Polo Square below so that each side adds to the same total.
Systematically explore the range of symmetric designs that can be created by shading parts of the motif below. Use normal square lattice paper to record your results.
This pair of linked Sudokus matches letters with numbers and hides a seasonal greeting. Can you find it?
Zumf makes spectacles for the residents of the planet Zargon, who have either 3 eyes or 4 eyes. How many lenses will Zumf need to make all the different orders for 9 families?
Suppose we allow ourselves to use three numbers less than 10 and multiply them together. How many different products can you find? How do you know you've got them all?
You cannot choose a selection of ice cream flavours that includes totally what someone has already chosen. Have a go and find all the different ways in which seven children can have ice cream.
What is the date in February 2002 where the 8 digits are palindromic if the date is written in the British way?
This Sudoku puzzle can be solved with the help of small clue-numbers on the border lines between pairs of neighbouring squares of the grid.
A Sudoku that uses transformations as supporting clues.