Over the past decade there has been increased focus on the mathematical preparation of teachers at all levels as one of the main tools in improving mathematics education in this country. The mathematical knowledge of teachers arguably involves not only solid procedural and conceptual mastery of key mathematical processes and phenomena, but also understanding how mathematics content fits into and extends the school curriculum. In their coursework and professional development, teachers need to experience the process of learning and doing mathematics: experimenting, conjecturing, justifying, generalizing. and struggling. Teachers also need to experience consistently the beauty and power of mathematics.

Middle school mathematics teachers occupy a unique place in the mathematical development of students. These teachers need to be proficient in all elementary mathematics topics, together with some secondary mathematics topics. They demand a special kind of preparation that differs from both that of their elementary and secondary colleagues. The Mathematics Education of Teachers (MET) document published by the Conference Board of the Mathematical Sciences set forth criteria for the preparation of mathematics middle school teachers which made it critical that special programs and courses for this group emerge. All middle school teachers need to know the mathematics content for elementary teachers. In addition, in the strand of number sense and operation, middle school teachers need to be fluent with the number line model for the real numbers, proportional reasoning, and elementary number theory.