Which is quicker, counting up to 30 in ones or counting up to 300 in tens? Why?
Which pairs of cogs let the coloured tooth touch every tooth on the
other cog? Which pairs do not let this happen? Why?
Help share out the biscuits the children have made.
Can you find any perfect numbers? Read this article to find out more...
This article for teachers describes how number arrays can be a
useful reprentation for many number concepts.
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.
For this challenge, you'll need to play Got It! Can you explain the
strategy for winning this game with any target?
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?
Norrie sees two lights flash at the same time, then one of them
flashes every 4th second, and the other flashes every 5th second.
How many times do they flash together during a whole minute?
Find the words hidden inside each of the circles by counting around
a certain number of spaces to find each letter in turn.
Factor track is not a race but a game of skill. The idea is to go
round the track in as few moves as possible, keeping to the rules.
What is the lowest number which always leaves a remainder of 1 when
divided by each of the numbers from 2 to 10?
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?
Frances and Rishi were given a bag of lollies. They shared them out evenly and had one left over. How many lollies could there have been in the bag?
Pat counts her sweets in different groups and both times she has
some left over. How many sweets could she have had?
How can you use just one weighing to find out which box contains
the lighter ten coins out of the ten boxes?
Ben and his mum are planting garlic. Use the interactivity to help
you find out how many cloves of garlic they might have had.
Can you see how these factor-multiple chains work? Find the chain
which contains the smallest possible numbers. How about the largest
Ben’s class were making cutting up number tracks. First they
cut them into twos and added up the numbers on each piece. What
patterns could they see?
An investigation that gives you the opportunity to make and justify
"Ip dip sky blue! Who's 'it'? It's you!" Where would you position
yourself so that you are 'it' if there are two players? Three
Investigate the sum of the numbers on the top and bottom faces of a line of three dice. What do you notice?
Look at three 'next door neighbours' amongst the counting numbers. Add them together. What do you notice?
Can you complete this calculation by filling in the missing numbers? In how many different ways can you do it?
Have a go at balancing this equation. Can you find different ways of doing it?
Can you work out some different ways to balance this equation?
I am thinking of three sets of numbers less than 101. Can you find
all the numbers in each set from these clues?
I am thinking of three sets of numbers less than 101. They are the
red set, the green set and the blue set. Can you find all the
numbers in the sets from these clues?
These red, yellow and blue spinners were each spun 45 times in
total. Can you work out which numbers are on each spinner?
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?
Can you find the chosen number from the grid using the clues?
A game that tests your understanding of remainders.
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?
Can you place the numbers from 1 to 10 in the grid?
I throw three dice and get 5, 3 and 2. Add the scores on the three
dice. What do you get? Now multiply the scores. What do you notice?
56 406 is the product of two consecutive numbers. What are these
48 is called an abundant number because it is less than the sum of
its factors (without itself). Can you find some more abundant
This big box multiplies anything that goes inside it by the same number. If you know the numbers that come out, what multiplication might be going on in the box?
Can you work out what a ziffle is on the planet Zargon?
Is it possible to draw a 5-pointed star without taking your pencil
off the paper? Is it possible to draw a 6-pointed star in the same
way without taking your pen off?
On the planet Vuv there are two sorts of creatures. The Zios have 3 legs and the Zepts have 7 legs. The great planetary explorer Nico counted 52 legs. How many Zios and how many Zepts were there?
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.
Work out Tom's number from the answers he gives his friend. He will
only answer 'yes' or 'no'.
Follow the clues to find the mystery number.
There are ten children in Becky's group. Can you find a set of
numbers for each of them? Are there any other sets?
Use cubes to continue making the numbers from 7 to 20. Are they sticks, rectangles or squares?
On a farm there were some hens and sheep. Altogether there were 8
heads and 22 feet. How many hens were there?
Place four pebbles on the sand in the form of a square. Keep adding
as few pebbles as necessary to double the area. How many extra
pebbles are added each time?
Look at the squares in this problem. What does the next square look
like? I draw a square with 81 little squares inside it. How long
and how wide is my square?
How many trains can you make which are the same length as Matt's,
using rods that are identical?