Background/purpose: 21st-century learning is an education reform that aims to equip every student with the essential skills to face global challenges. One of the strategies to tackle global challenges is teaching English as a Foreign Language (EFL) students the four key elements of 4Cs: creativity, critical thinking, communication, and collaboration. However, the availability of English instructional materials is limited. Therefore, the present study aims to develop student and teacher model books that integrate 4C skills. Hence, teachers can design and develop English instructional materials. Materials/methods: Research and development (R&D) was conducted in four steps: need analysis and problem identification, model development, model implementation, and model evaluation. The research involved three types of research participants: one class of university students consisting of 20 students, five experts, and 2 teachers. The research applied semi-structured interviews, a questionnaire, and a test. Results: The findings reveal that the participants need students' and teachers' model books that integrate 4C skills. Furthermore, the proposed model books were proven to be very valid, very practical, and effective. The findings also mentioned that the model books very much include 4C skills. Conclusion: Designing and developing model books can further improve not only students' academic achievement but also their skills. It is recommended that teachers design and build their own model book for their own courses. Thus, preparing and training teachers on material development is of paramount significance.