Creativity, as a 21st-century skill, has gained more interest these past years and has become one of the key competencies to be implemented in classrooms. However, some studies highlight teachers’ difficulties to integrate it in a classroom context. For instance, introducing creativity in overloaded school curricula may be a hindrance to developing it. Teachers have to implement other 21st-century competencies (the 4Cs) at the same time as well. These educational objectives can be considerable in terms of time and means for teachers and thus do not encourage them to develop these competencies. The purpose of this article is to present links, essentially theoretical, made by researchers between creativity and other 21st-century skills (e.g., critical thinking, metacognition, and collaboration). We considered that if creativity shares some characteristics with other competencies, it can be possible that, by applying only a teaching-for-creativity approach in classroom, we can also contribute to developing the other “C” as well. So choosing only creativity can be a way for teachers to develop their pupils’ skills without falling behind in their curriculum. In this article, we will also discuss our hypothesis taking into account limits from teachers’ classroom practices. Teachers’ training, evaluation, and everyday practices will be considered.