A church hymn book contains 700 hymns. The numbers of the hymns are
displayed by combining special small single-digit boards. What is
the minimum number of small boards that is needed?
This is a game in which your counters move in a spiral round the snail's shell. It is about understanding tens and units.
The Scot, John Napier, invented these strips about 400 years ago to
help calculate multiplication and division. Can you work out how to
use Napier's bones to find the answer to these multiplications?
Find out what a Deca Tree is and then work out how many leaves
there will be after the woodcutter has cut off a trunk, a branch, a
twig and a leaf.
What do the digits in the number fifteen add up to? How many other
numbers have digits with the same total but no zeros?
In the multiplication sum, some of the digits have been replaced by letters and others by asterisks. Can you reconstruct the original multiplication?
Four of these clues are needed to find the chosen number on this
grid and four are true but do nothing to help in finding the
number. Can you sort out the clues and find the number?
Can you find the chosen number from the grid using the clues?
Which is quicker, counting up to 30 in ones or counting up to 300 in tens? Why?
In this 100 square, look at the green square which contains the numbers 2, 3, 12 and 13. What is the sum of the numbers that are diagonally opposite each other? What do you notice?
These spinners will give you the tens and unit digits of a number. Can you choose sets of numbers to collect so that you spin six numbers belonging to your sets in as few spins as possible?
Becky created a number plumber which multiplies by 5 and subtracts
4. What do you notice about the numbers that it produces? Can you
explain your findings?
You have two sets of the digits 0 – 9. Can you arrange these
in the five boxes to make four-digit numbers as close to the target
numbers as possible?
Follow the clues to find the mystery number.
Can you replace the letters with numbers? Is there only one
solution in each case?
This multiplication uses each of the digits 0 - 9 once and once only. Using the information given, can you replace the stars in the calculation with figures?
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.
Can you substitute numbers for the letters in these sums?
Find the sum of all three-digit numbers each of whose digits is
If you put three beads onto a tens/ones abacus you could make the
numbers 3, 30, 12 or 21. What numbers can be made with six beads?
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?
You have a set of the digits from 0 – 9. Can you arrange
these in the 5 boxes to make two-digit numbers as close to the
targets as possible?
How would you create the largest possible two-digit even number
from the digit I've given you and one of your choice?
There are nasty versions of this dice game but we'll start with the nice ones...
This 100 square jigsaw is written in code. It starts with 1 and
ends with 100. Can you build it up?
Each child in Class 3 took four numbers out of the bag. Who had
made the highest even number?
I am less than 25. My ones digit is twice my tens digit. My digits
add up to an even number.
There are six numbers written in five different scripts. Can you
sort out which is which?
Exploring the structure of a number square: how quickly can you put the number tiles in the right place on the grid?
How many solutions can you find to this sum? Each of the different letters stands for a different number.
Lee was writing all the counting numbers from 1 to 20. She stopped
for a rest after writing seventeen digits. What was the last number
Investigate the different ways these aliens count in this
challenge. You could start by thinking about how each of them would
write our number 7.
Marion Bond recommends that children should be allowed to use
'apparatus', so that they can physically handle the numbers
involved in their calculations, for longer, or across a wider
ability band,. . . .
This article, written for teachers, looks at the different kinds of
recordings encountered in Primary Mathematics lessons and the
importance of not jumping to conclusions!
Who said that adding, subtracting, multiplying and dividing
couldn't be fun?
A game to be played against the computer, or in groups. Pick a 7-digit number. A random digit is generated. What must you subract to remove the digit from your number? the first to zero wins.
Nowadays the calculator is very familiar to many of us. What did
people do to save time working out more difficult problems before
the calculator existed?
Once a basic number sense has developed for numbers up to ten, a
strong 'sense of ten' needs to be developed as a foundation for
both place value and mental calculations.
This article for the young and old talks about the origins of our number system and the important role zero has to play in it.
Investigate which numbers make these lights come on. What is the smallest number you can find that lights up all the lights?