Although active learning is highly recognized and recommended in the educational community, instructors are still struggling with how to incorporate active learning tools into writing courses. This study aims to 1) describe specific challenges encountered in the course of Molecular Cell Biology Laboratory--Critical Thinking through Writing (BIOL3810-CTW); 2) introduce the active learning approaches and metacognition integrated into this writing-intensive course; 3) demonstrate the effectiveness of these active learning approaches in engaging students in classes; and 4) share the principles of integrating active learning activities into writing courses in science, technology, engineering, and mathematics (STEM) and beyond.