Euclid’s Elements is the most published book in human history after the Bible. Before the 20th century, reading Euclid would have been a normal part of a student’s education in Mathematics. Why did exposure to Euclid cease, and perhaps more importantly, what did we put in its place? As Classical educators we are very careful about the philosophical assumptions which underlie our pedagogy. This session will examine the differing assumptions behind a Pre-Modern approach to Mathematics and a Post-Cartesian one and then, using Euclid as a model, will explore practical ways to recover a more Classical form of Math instruction for K-12th students.