Description ① A 5-step learning process: Preparation → Principles → Mastery → Speed → Accuracy ② A self-study system that helps children discover math principles and methods on their own. This is Yeonsan C2 (Elementary 3rd Grade Course), designed to help students become faster and stronger in math, is a workbook that builds computation skills through a 5-step learning system. Before starting math practice, students first build self-directed learning habits by sparking interest and motivation. Next, they learn the underlying principles behind each type of calculation. Through repeated practice, they deepen their understanding until they can confidently master the process, and finally, by solving a variety of problems, they improve accuracy and precision.