In mathematics education our primary focus tends to be how to approach the concepts we teach, taking for granted the choice of subjects that enter the syllabus. Traditionally, the way the standards are determined follows a specific philosophical inclination: school mathematics is still predominantly galilean. It is viewed as a language with which to understand and describe objects and patterns we experience in the world. Math is still viewed as a vehicle for the expression of explanatory models of reality. That's how we define what knowledge is necessary (and thus mandatory): you can't describe movement without functions, you can't solve problems without algebra. Math is the list of things you (supposedly) can't go without in order to understand how the world works.
It can be argued that the developments in contemporary mathematics favor a more transformative, or "creative" approach to mathematical thinking. The mathematical foundations of visualization techniques, robotics, modern design, software engineering, cryptography, etc., do not deal with merely understanding, but mostly with producing new ideas, and new things. Math would be the way to express proposals. Still a language, but for writing "fiction".
My question is: assuming this change in perspective affects the way we teach math in school, how will it impact the way we define and organize the contents we will be working with, in the years to come? More specifically, how will we determine what is mandatory for the students of tomorrow?