Today, instead of individuals who memorizing knowledge, it is aimed to educate, scientific literacy, individuals who search and question knowledge. One of the increasingly important processes in the process of scientific literacy individual training is argumentation (Öğreten & Uluçınar-Sağır, 2014). Arguments are structures used to support claims. The process that these structures create is an argumentation (Sampson & Clark, 2008). According to Thoron and Myers (2012), argumentation is the process by which individuals produce allegations and prove different results. According to Akpınar and Ergin (2005), the activeness of the students in Science courses and their work as a scientist will prevent the science concepts from becoming a mass of memorization and the concepts will be more understandable. Successful teaching is realized because the use of argumentation in the teaching process enables individuals to freely express their ideas and defend their claims with supportive and disinfective means (Kaya & Kılıç, 2010). In the research, it was aimed to analyze the levels of the written scientific arguments that the 7th grade Science students produced in terms of the activities about the Sense Organs in the context of the Toulmin argumentation model. In the study, case studies from qualitative research methods were used as methods. The study was conducted with 28 students studying in the 7th class. In the study, study pages (consisting of 4 separate activities) where open-ended questions related to the subject of Sensory Organs prepared by the researcher were used as data collection tool. In the prepared events, students are asked to think individually and respond to open-ended questions in the activities Later on, they made activities and shared their observations and ideas with their group of friends. In this process, students have been supported in places where they need to use reasoning and refuting expressions. In order to determine the levels of the students' arguments that they produced during the events, the argument evaluation scale established by Sadler and Fowler (2006) in the literature was used. The arguments that the students put in writing are analyzed and coded according to the evaluation scale. In addition to the researcher, the written arguments have also been evaluated by an expert with knowledge of the argumentation to check the credibility of the coding made. The content of the students' produced articles about the activities was examined and analyzed according to the Toulmin Argumentation Model components claim, data, reason and refusing. During the data analysis process, the level of the arguments the students produced and the number of learners who made the argument were determined. According to the study of the ability of the 7th grade students to make arguments on the Sense Organs, students can make claims about the activities but have difficulties in supporting their claims. It has been seen that students generally try to support their claims for simple reasons and cannot use refractors. Sim Duyu Organları Konusu ile İlgili Argümanlar | 263 ilarly, Dawson and Venville (2009) examined the ability of students aged 1217 to create arguments, and found that students were able to find arguments on the subject, but not to explain their arguments. In this study, it was determined that during the act ivities the students used the claim item more than the other argument items. According to this, it can be said that the students in the study group have low level of argument and not much development. Similarly, in his study of Kuhn (1991), he argued that students had argumentation skills but that these skills did not improve. Apaydın, AymenPeker and Taş (2012), in their work with grade 6 students and Akgün et al. (2014) in his work with 8 grade students; they found that students made claims and ration ale but failed to produce refutable expression in their research. Aslan (2012), in his work with the 9th, 10th, 11th and 12th graders, also examined the students' levels of argumentation and stated that the students made the claims they required but did no t fulfil their claims. In addition, it has been found that some of the 10th grade students have higher levels of argumentation than the 11th grade students. In some areas, such as the fingers, palms, where the tips of the items are pressed, there are more sensory receptors that perceive the press. intense Therefore, students should be stressed that they can feel together 2 times, while the students answered "as the distance was getting close to the point of pain (pressure) and 2 items were felt alone", “The pressure can be the reason for feeling alone, but we could not feel it if we did the back