Ucar, SerpiYazici, Yeliz2025-03-232025-03-2320161877-0428https://doi.org/10.1016/j.sbspro.2016.10.001https://hdl.handle.net/11486/6046International Conference on Teaching and Learning English as an Additional Language (GlobELT) -- APR 14-17, 2016 -- Antalya, TURKEYThis study aimed to investigate the effect of portfolios on developing writing skills among 52 Turkish undergraduate learners in ESP classes. This study was carried out on two groups experimental and control groups- each of which consists of 26 students. The learners were freshmen at the department of Sea and Marine Management at Vocational School of Higher Education, Sinop University. Before the treatment, a pre-test was administered to both groups in order to investigate the writing performance and sub skills of focus, elaboration, organization, conventions and vocabulary of learners of ESP. Throughout the study the experimental group was taught through portfolio assessment technique and the control group was taught through the conventional method. An Independent samples t-test was applied in order to see whether there was a statistically significant difference or not between the groups. Additionally, a Paired Samples t-test was used so as to compare differences within each group. The results obtained from the post-test demonstrated that there was a statistically significant difference between the experimental and control groups in terms of the type of treatment, which signifies that portfolios had a statistically significant effect on promoting writing performance and its sub skills in ESP classes. After the treatment, the students in the experimental group were also administered an attitude questionnaire to elicit their thoughts about the effectiveness of using portfolios on augmenting writing abilities in ESP classes. The data collected from the attitude questionnaire was analysed through descriptive statistics including the frequencies, percentages, means, and standard deviations etc. The results showed that students have positive attitudes towards using portfolios on improving their writing skills in ESP classes. (C) 2016 The Authors. Published by Elsevier Ltd.eninfo:eu-repo/semantics/openAccessPortfolioswriting performanceEnglish for specific purposesConference Object23222623310.1016/j.sbspro.2016.10.001N/AWOS:000387499800030N/A