The change of emphasis brings a change of direction which implies and requires a balance between:

• the process of being a mathematician, and
• the development of skills needed to be a successful mathematician.

This journey is not two paths. It is one path made of two interwoven threads in the same way as DNA, the building block of life, is one compound made of two interwoven coils.

Maths300 provides a rich resource of lessons, all prepared and trialed by classroom teachers, which is intended to support teacher teams in building the balance which is Working Mathematically in their school. Content skills are important, but it is the application of skills within the process of Working Mathematically which has developed, and is developing, the human community's mathematical knowledge.

A guiding principle of Working Mathematically is that we are all 'born' with the same size mathematical toolbox, in the same way as I can own the same size toolbox as my motor mechanic. However, my motor mechanic has many more tools in her box than I and she has had more experience than I using them in context. Someone has helped her learn to use those tools while crawling under a car. A focus for the Working Mathematically teacher is to help students develop mathematical skills in the context of problem posing and solving.

Afzal Ahmed, one time professor of mathematics at Chichester, UK, once quipped:

If teachers of mathematics had to teach soccer, they would start off with a lesson on kicking the ball, follow it with lessons on trapping the ball and end with a lesson on heading the ball. At no time would they play a game of football.

Such is not the case when teaching a Working Mathematically curriculum.