To raise scientifically literate people, countries give importance to the science education. However, not only in schools but in everywhere students can learn science. According to Falk and Dierking (2000), learning cannot occur only in the laboratory isolated from world, in fact it occurs with the integrated experiences in the real world such as science museums, science centers, zoos, aquariums, natural history museums, radio, television, Internet, books and games (Falk & Dierking, 2002, p.12). In this regard, the studies about informal science learning take researchers’ attention and have increased in past decades. On the other hand, research trend studies are important. They provide recent trends and give opinion about the research gaps in the literature. According to Chang, Chang and Tseng (2010), it is vital to understand what researchers studied in the past because these studies give an opinion about future research.For that reason, in order to reveal research trends in informal science learning and hope to help future research directions, the researchers conducted the current study. The aim of the current study was to analyze three selected journals which are Journal of Research in Science Teaching, International Journal of Science Education (IJSE): Part B and Visitor Studies from 2008 to 2017. Although there exist research trends studies related to informal science learning, this study is highly significant because researchers examined one major journal in science education research (JRST) and two major journals directly related with informal science learning (IJSE: Part B and Visitor Studies). Different from past studies, researchers analyzed research contexts, sample type and data collection tools. The rationale for analyzing context is to reveal what informal learning contexts should be studied more for the future research. In addition, the rationale for analyzing sample type is to show most studied and least studies research groups in informal science learning. The followings were the research questions for this study; (1) What was the distribution of published articles in terms of years? (2) What was the distribution of published articles in terms of author’s nationality? (3) Which research categories/topics were frequently used in the selected journals? (4) Which research methods were frequently used by researchers in the selected journals? (5) What types of samples were frequently preferred by researchers in the selected journals? (6) What type of data collection tools were frequently used in the selected journals? (7) Which informal science contexts were frequently used by researchers in the selected journals?

The sample consisted 136 articles published in IJSE: Part B, JRST and Visitor Studies from 2008 to 2017. Qualitative methodology was used for this study. According to Fraenkel et al., content analysis is the analysis of written contents such as articles, books, textbooks and so on (2012, p.478). Therefore, in order to analyze research trends in informal science education, researchers used content analysis for selected journals. To ensure reliability, articles were examined by another researcher who is more experienced and knowledgeable in the science education field. In order to investigate trends in informal science education, researchers used keywords including “informal”, “out of school”, “science center”, “museum”, “field trip” and “school visit”. In addition, book reviews, letters to editors, literature reviews, reflections and commentaries were excluded from the analysis because the main purpose was to analyze researches related to informal science learning. Authors’ nationality was analyzed according to formula of Howard et al. (1987) and study of Tsai and Wen (2005). In the formula, it was accepted that each paper has one point. If there is one author, this author’s nation will get 1. On the contrary, if there are two authors, the score will be distributed respectively as a 0.6 and 0.4. In addition, the categorization of research topics adapted from Pinthong and Faikhamta’s (2017) study. Accordingly, there exist eight categories: (1) Public Understanding in Science; (2) Informal Learning Context Development; (3) Informal Science Education for Professional Development; (4) Teaching and Students’ Learning in Informal Context; (5) Students’ Informal Learning; (6) Informal Perspectives, Policies and Paradigms; (7) Science in Community; (8) Informal Science Educator Professional Development.

Although there existed slight fluctuations, total number of the published articles were increased from 2008 to 2017. 2014 can be considered as most productive year with the total 24 published research papers. Between 2008 and 2017, authors from USA were published articles most with the score of 72.78 (n = 136). In other words, more than half of the papers were written by USA researches (53.5 %). At this stage, other countries should give emphasis to the informal science learning. The analysis showed that researches mostly focused on two categories: Public Understanding in Science (f = 35) and Students’ Informal Learning (f = 35). In contrast, researches were very few in the Informal Science Education for Professional Development (f = 5) and Teaching and Students’ Learning in Informal Context (f = 6) categories. Research method analysis implied that qualitative methods were used more (f = 63). While considering sample of the articles, students were researched most (f = 58) and teacher were less (f = 13). Researchers used variety of data collection tools including interviews (f= 68), questionnaire (f = 43) and observation (f = 40). The total frequency of 231 data collection tools in 136 papers showed that researchers used more than one tool in some studies. Science centers (f= 53) and other informal contexts (f= 49) such as science clubs, camps, personal hobbies were examined most. Researchers suggest improving research in the context of TV and Internet because people use them more because of the widespread of the technology.

Chang, Y. H., Chang, C. Y., & Tseng, Y. H. (2010). Trends of science education research: An automatic content analysis. Journal of Science Education and Technology, 19(4), 315-331. DeBoer, G. E. (2000). Scientific literacy: Another look at its historical and contemporary meanings and its relationship to science education reform. Journal of Research in Science Teaching: The Official Journal of the National Association for Research in Science Teaching, 37(6), 582-601. Falk, J. H., & Dierking, L. D. (2000). Learning from museums. Walnut Creek. Falk, J. H., & Dierking, L. D. (2002). Lessons without limit: How free-choice learning is transforming education. Rowman Altamira. Falk, J.H., Osborne, J., Dierking, L., Dawson, E., Wenger, M., & Wong, B. (2012) Analysing the UK science education community: The contribution of informal providers. London:Wellcome Trust. Fraenkel, J. R., Wallen, N. E., & Hyun, H. H. (2012). How to design and evaluate research in education. New York: McGraw-Hill Humanities/Social Sciences/Languages. Howard, G. S., Cole, D. A., & Maxwell, S. E. (1987). Research productivity in psychology based on publication in the journals of the American psychological association. American Psychologist, 42(11), 975. InCites Journal Citation Report, Clarivate Analytics (2017). Retrieved from http://jcr.incites.thomsonreuters.com/JCRJournalProfileAction.action?pg=JRNLPROF&journalImpactFactor=n%2Fa&year=2017&journalTitle=J%20RES%20SCI%20TEACH&edition=SSCI&journal=J%20RES%20SCI%20TEACH Phipps, M. (2010). Research trends and findings from a decade (1997–2007) of research on informal science education and free-choice science learning. Visitor studies, 13(1), 3-22. Tsai, C. C., & Lydia Wen, M. (2005). Research and trends in science education from 1998 to 2002: A content analysis of publication in selected journals. International journal of science education, 27(1), 3-14.