In the start, just after children are getting used to numbers, to introduce symbols to represent numbers might seem a bit much.

But what are numbers if not symbols in any case. Youngsters may have trouble writing or drawing their numbers but this would be an opportunity to give them a sense of equality - one person's representation of a number could be seen as good as another's.

They concept is more than just swapping numbers for letters, it is to try to get over that a letter could represent any value - we just don't know it yet.

To give an idea of this we can come up with the idea of a box, and in this box we'll place a number. We can start with putting in a random amount of objects (e.g. coins, buttons, and sweets). This gives an opportunity for counting.

This could lead to a picture of a box. The box could fit into an expression. For example, whatever is in the box plus 5 makes 10. Other arithmetic machines could be introduced to practise 'solving algebra'.