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?
Suppose we allow ourselves to use three numbers less than 10 and
multiply them together. How many different products can you find?
How do you know you've got them all?
Investigate the different shaped bracelets you could make from 18 different spherical beads. How do they compare if you use 24 beads?
The first person who is unable
to cross out a number loses.
Here is an interactive version of the game in which you drag the
numbers from the left hand grid and drop them on the right hand
grid. Alternatively, click on a number in the left hand grid and it
will transport to the earliest empty location in the right hand
grid. You can rearrange the numbers in the right hand grid by
dragging and dropping them in position. The integer in the top
right hand corner grows with the number of factors/multiples you
have in a row.