Knowing By Number: Learning Math for Thinking Well

•The controversy of the Common Core State Standards for mathematics is just the latest in a long history of disagreements about the content and nature of mathematics education.•Math is the discipline that disciplines the mind-and the math classroom is widely understood as a venue for debate about how citizens should be trained to think.•By considering the history of curricular reforms, particularly the mid-century “new math” movement, we might better understand ongoing debates about the control and content of math education.