The first player chooses a positive even number that is less than 50, and crosses it out on the 100 square grid.
The second player chooses a number to cross out. The number must be a factor or multiple of the previous number.
You might like to start by investigating the patterns you get when you shade multiples of a number on a grid. Download here
For the prime sieve investigation use a 100 square grid (download here):
Circle the number 2. Put a line through every multiple of 2 up to 100.
See the Inclusion and Home Learning Guide for related activities on the same topic for ages 4 to 18+.
How many factors does 72 have?
Investigate numbers that are products of a square number and a cube number. How many factors do they have?
How does the number 1 behave in the world […]
When you turn this star around it looks exactly the same in 5 different positions so we say it has ROTATIONAL SYMMETRY of order 5.
Is it possible to draw a 6-pointed star in the same way […]
One of three columns of tally marks on The Ishango Bone gives the answer to this question. Found in the Ishango region of the Democratic Republic of […]
These counting games lead to an understanding of multiples and common multiples, number patterns and the Sieve of Eratosthenes to find prime numbers.
Click here to download a pdf with all you need to run your own professional development workshop.
Describe and explain this pattern.
Download this sheet and shade in the patterns of the multiples.
Why do you think that in each pattern […]
Multiply any two consecutive even numbers together. Why is the product always a multiple of eight?
Take any prime number greater than 3, square it, subtract one and divide by 24.
Make a […]