Which of the following is not one of the three math models?

The correct choice identifies the Direct Instruction Model as not being one of the three math models. The three established models for teaching mathematics typically include concepts from the National Council of Teachers of Mathematics (NCTM), which supports standards-based math education, and the Common Core State Standards, which provide a clear framework for what students should learn in math at each grade level. The Spiral Topic approach is commonly used as well, emphasizing revisiting topics over time to deepen understanding.

In contrast, the Direct Instruction Model focuses on a highly structured, teacher-led approach to instruction, primarily based on scripted lessons and immediate feedback, rather than a model specifically for mathematics education. It is more a teaching strategy than a math model in the context of curriculum development or educational standards. Thus, understanding the distinct roles of these approaches clarifies why the Direct Instruction Model does not belong to the classification of recognized math models.