In an effort to understand how a teacher developed Mathematical Knowledge for Teaching and how that knowledge can shift teacher's beliefs and instructional practice, I worked with a teacher to deeply plan and implement six mathematical lessons.;The research suggests that planning can be a vehicle to develop a teacher's Mathematical Knowledge for Teaching. In addition, as a teacher's Mathematical Knowledge for Teaching started to develop through lesson planning, the teacher's beliefs about her own knowledge of mathematics started to increase which started to shift the teacher's instructional practice.;This combination of a stronger Mathematical Knowledge for Teaching, self confidence in her own understanding of the mathematics and shifts in her instructional practice created a new pedagogical practice I have called The Pedagogy of Knowing. |