This document discusses strategies for developing 21st century skills in students through creative problem solving classes and a flipped classroom model. It outlines steps for renovating a classroom, including pre-class, in-class, and post-class activities to promote active and autonomous learning. Examples of in-class activities that develop creative problem solving skills are provided, such as coached problem solving, collaborative learning, and project-based learning. The goals are to motivate students' thinking skills and help them crystallize their implicit knowledge by exploring knowledge in virtual scenarios in a flipped classroom.