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?
Can you see why 2 by 2 could be 5? Can you predict what 2 by 10
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!
Choose a symbol to put into the number sentence.
Start by putting one million (1 000 000) into the display of your
calculator. Can you reduce this to 7 using just the 7 key and add,
subtract, multiply, divide and equals as many times as you like?
Can you put the numbers 1 to 8 into the circles so that the four
calculations are correct?
Make one big triangle so the numbers that touch on the small triangles add to 10. You could use the interactivity to help you.
Imagine a pyramid which is built in square layers of small cubes. If we number the cubes from the top, starting with 1, can you picture which cubes are directly below this first cube?
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?
Can you hang weights in the right place to make the equaliser
If you have only four weights, where could you place them in order
to balance this equaliser?
Place the numbers 1 to 10 in the circles so that each number is the
difference between the two numbers just below it.
Use the information about Sally and her brother to find out how many children there are in the Brown family.
Find your way through the grid starting at 2 and following these
operations. What number do you end on?
Make your own double-sided magic square. But can you complete both
sides once you've made the pieces?
Choose four of the numbers from 1 to 9 to put in the squares so that the differences between joined squares are odd.
Place the numbers 1 to 6 in the circles so that each number is the
difference between the two numbers just below it.
In a square in which the houses are evenly spaced, numbers 3 and 10
are opposite each other. What is the smallest and what is the
largest possible number of houses in the square?
In your bank, you have three types of coins. The number of spots shows how much they are worth. Can you choose coins to exchange with the groups given to make the same total?
Here is a chance to play a version of the classic Countdown Game.
Choose four different digits from 1-9 and put one in each box so that the resulting four two-digit numbers add to a total of 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?
Can you make a train the same length as Laura's but using three differently coloured rods? Is there only one way of doing it?
Place six toy ladybirds into the box so that there are two ladybirds in every column and every row.
Use the interactivities to fill in these Carroll diagrams. How do you know where to place the numbers?
Can you each work out the number on your card? What do you notice?
How could you sort the cards?
This challenge extends the Plants investigation so now four or more children are involved.
How have the numbers been placed in this Carroll diagram? Which labels would you put on each row and column?
Here you see the front and back views of a dodecahedron. Each
vertex has been numbered so that the numbers around each pentagonal
face add up to 65. Can you find all the missing numbers?
There are to be 6 homes built on a new development site. They could
be semi-detached, detached or terraced houses. How many different
combinations of these can you find?
We start with one yellow cube and build around it to make a 3x3x3 cube with red cubes. Then we build around that red cube with blue cubes and so on. How many cubes of each colour have we used?
The idea of this game is to add or subtract the two numbers on the dice and cover the result on the grid, trying to get a line of three. Are there some numbers that are good to aim for?
This article gives you a few ideas for understanding the Got It! game and how you might find a winning strategy.
First Connect Three game for an adult and child. Use the dice numbers and either addition or subtraction to get three numbers in a straight line.
If you hang two weights on one side of this balance, in how many different ways can you hang three weights on the other side for it to be balanced?
Ahmed is making rods using different numbers of cubes. Which rod is twice the length of his first rod?
This challenging activity involves finding different ways to distribute fifteen items among four sets, when the sets must include three, four, five and six items.
Can you use the numbers on the dice to reach your end of the number line before your partner beats you?
Use the number weights to find different ways of balancing the equaliser.
Have a go at this game which involves throwing two dice and adding
their totals. Where should you place your counters to be more
likely to win?
A game for 2 people using a pack of cards Turn over 2 cards and try
to make an odd number or a multiple of 3.
Katie had a pack of 20 cards numbered from 1 to 20. She arranged
the cards into 6 unequal piles where each pile added to the same
total. What was the total and how could this be done?
Lolla bought a balloon at the circus. She gave the clown six coins
to pay for it. What could Lolla have paid for the balloon?
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?
Move from the START to the FINISH by moving across or down to the
next square. Can you find a route to make these totals?
Can you substitute numbers for the letters in these sums?
A game for 2 people. Use your skills of addition, subtraction, multiplication and division to blast the asteroids.
An investigation involving adding and subtracting sets of consecutive numbers. Lots to find out, lots to explore.
Throw the dice and decide whether to double or halve the number. Will you be the first to reach the target?
Who said that adding couldn't be fun?