Critical thinking and problem solving, communication, collaboration, and creativity (the 4Cs) are 21st century skills that are important for students to develop. Critical thinking involves using reasoning and evidence to make conclusions. It is connected to other skills like creativity. Communication skills allow students to clearly express ideas. Collaboration emphasizes working together respectfully and valuing each other's contributions. Creativity involves generating new ideas and being innovative. All the 4Cs are interrelated and can be developed through activities like debates, project-based learning, and using technology like blogs and video conferencing. Resources like rubrics and online programs provide ways to integrate these skills into classroom lessons.