In this activity, the computer chooses a times table and shifts it. Can you work out the table and the shift each time?
Imagine a wheel with different markings painted on it at regular
intervals. Can you predict the colour of the 18th mark? The 100th
Arrange the four number cards on the grid, according to the rules, to make a diagonal, vertical or horizontal line.
Can you find a relationship between the number of dots on the
circle and the number of steps that will ensure that all points are
Can you find a reliable strategy for choosing coordinates that will locate the robber in the minimum number of guesses?
Can you complete this jigsaw of the multiplication square?
Starting with the number 180, take away 9 again and again, joining up the dots as you go. Watch out - don't join all the dots!
Mr McGregor has a magic potting shed. Overnight, the number of
plants in it doubles. He'd like to put the same number of plants in
each of three gardens, planting one garden each day. Can he do it?
Here is a chance to play a version of the classic Countdown Game.
Use the interactivity to create some steady rhythms. How could you
create a rhythm which sounds the same forwards as it does
If you have only four weights, where could you place them in order
to balance this equaliser?
What do the numbers shaded in blue on this hundred square have in common? What do you notice about the pink numbers? How about the shaded numbers in the other squares?
Try entering different sets of numbers in the number pyramids. How does the total at the top change?
Draw some isosceles triangles with an area of $9$cm$^2$ and a vertex at (20,20). If all the vertices must have whole number coordinates, how many is it possible to draw?
A card pairing game involving knowledge of simple ratio.
Investigate the smallest number of moves it takes to turn these
mats upside-down if you can only turn exactly three at a time.
Work out how to light up the single light. What's the rule?
Use the interactivity to find all the different right-angled triangles you can make by just moving one corner of the starting triangle.
Each light in this interactivity turns on according to a rule. What happens when you enter different numbers? Can you find the smallest number that lights up all four lights?
This article gives you a few ideas for understanding the Got It! game and how you might find a winning strategy.
Can you spot the similarities between this game and other games you know? The aim is to choose 3 numbers that total 15.
Semi-regular tessellations combine two or more different regular polygons to fill the plane. Can you find all the semi-regular tessellations?
A tetromino is made up of four squares joined edge to edge. Can
this tetromino, together with 15 copies of itself, be used to cover
an eight by eight chessboard?
Have a go at this well-known challenge. Can you swap the frogs and toads in as few slides and jumps as possible?
Cut four triangles from a square as shown in the picture. How many
different shapes can you make by fitting the four triangles back
Hover your mouse over the counters to see which ones will be
removed. Click to remover them. The winner is the last one to
remove a counter. How you can make sure you win?
Place six toy ladybirds into the box so that there are two ladybirds in every column and every row.
Try out the lottery that is played in a far-away land. What is the
chance of winning?
An environment which simulates working with Cuisenaire rods.
Use the interactivities to complete these Venn diagrams.
Can you put the numbers 1 to 8 into the circles so that the four
calculations are correct?
A game for 2 people that everybody knows. You can play with a
friend or online. If you play correctly you never lose!
An interactive activity for one to experiment with a tricky tessellation
An interactive game for 1 person. You are given a rectangle with 50 squares on it. Roll the dice to get a percentage between 2 and 100. How many squares is this? Keep going until you get 100. . . .
This problem is based on a code using two different prime numbers
less than 10. You'll need to multiply them together and shift the
alphabet forwards by the result. Can you decipher the code?
What are the coordinates of the coloured dots that mark out the
tangram? Try changing the position of the origin. What happens to
the coordinates now?
Our 2008 Advent Calendar has a 'Making Maths' activity for every
day in the run-up to Christmas.
A and B are two interlocking cogwheels having p teeth and q teeth respectively. One tooth on B is painted red. Find the values of p and q for which the red tooth on B contacts every gap on the. . . .
Can you make a cycle of pairs that add to make a square number
using all the numbers in the box below, once and once only?
A generic circular pegboard resource.
Place the numbers 1 to 10 in the circles so that each number is the
difference between the two numbers just below it.
Choose a symbol to put into the number sentence.
Practise your diamond mining skills and your x,y coordination in this homage to Pacman.
A game for two people, or play online. Given a target number, say 23, and a range of numbers to choose from, say 1-4, players take it in turns to add to the running total to hit their target.
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?
A game for 2 people that can be played on line or with pens and paper. Combine your knowledege of coordinates with your skills of strategic thinking.
Choose 13 spots on the grid. Can you work out the scoring system? What is the maximum possible score?
Interactive game. Set your own level of challenge, practise your table skills and beat your previous best score.
Is it possible to place 2 counters on the 3 by 3 grid so that there
is an even number of counters in every row and every column? How
about if you have 3 counters or 4 counters or....?
NRICH December 2006 advent calendar - a new tangram for each day in
the run-up to Christmas.