Students in all types of education often have difficulty acquiring topic knowledge and insight into subject matter of various disciplines. They do not understand or cannot remember theory from their textbook. Usually, students learn theory by studying textbooks, by listening closely to their teacher's explanations, or by discussing subject matter with peers. However, this is often not enough to get a grip on subject matter. Writing-to-learn can help; however, this way of learning is not yet much applied in education. In writing-to-learn, the aim is to promote learning by writing texts about subject matter. This allows students to reread their written knowledge and to reflect whether they have displayed the disciplinary content correctly. Writing-to-learn is writing with the aim to gain insight into subject matter and to acquire topic knowledge.