Peer Instruction in a Flipped Learning Environment: Investigating ESL Students’ Critical Thinking Performance in Argumentative Essay Writing

Research shows that peer instruction and flipped learning help ESL/EFL students compensate for their shortcomings in their language, support the language learning process, and facilitate social interactions and collaboration between teachers and students in the class. Despite this, there has been little research into whether upper-intermediate ESL students can benefit from the use of peer instruction in a flipped learning environment in enhancing critical thinking performance in argumentative essay writing. This current study tests this hypothesis. A total of 120 English Proficiency 4 (EP4) students from a teacher education university in Malaysia were equally divided into two experimental groups (pair work and group work) and a control group (conventional teaching method). The experimental groups’ activities included a focus on different modes of peer instruction (pair work/group work) and flipped learning, while the control groups did not. Two research instruments were employed in this study: preand post-tests and a holistic scoring rubric. The critical thinking aspect was adapted from Stapleton and Wu (2015) and Toulmin’s model of argumentation (2003). Descriptive and inferential statistics, namely, one-way analysis of variance (ANOVA) was computed using IBM SPSS Statistics 26. Overall, compared to the control group, both experimental groups (pair work and group work) performed better in mean scores for critical thinking in the posttest. The result of the study suggests that the use of peer instruction in a flipped learning environment can be an alternative teaching method to enhance the students’ critical thinking in argumentative essay writing and offer implications for ESL students, language instructors, and researchers.


INTRODUCTION
The rapid development of the Malaysian higher education system has focused on the creation of flexible and futuristic learning spaces, promoted transformative learning and teaching delivery, and emphasised the importance of 21 st century skills and higher-order thinking skills (Ministry of Education Malaysia, 2015;Ministry of Higher Education Malaysia, 2018). Consequently, the field of English language teaching (ELT) has also undergone tremendous changes over the years in terms of emerging trends and teaching methodologies, Amreet Kaur Jageer Singh, Raja Nor Safinas Raja Harun Peer Instruction in a Flipped Learning Environment: Investigating ESL Students' Critical Thinking Performance in Argumentative Essay Writing DOI: https://doi.org/10. 31605/eduvelop.v4i2.986 namely, from a traditional method (teacher-centred approach) to a modern, technology-based, and interactive method (student-centred approach) (Badjadi, 2020;Jacobs & Renandya, 2016). This socalled paradigm shift and pedagogical transformation aim to increase and encourage active participation of students in the teaching and learning of English language. In relation to that, both flipped learning approach and peer instruction technique are growing rapidly in the teaching and learning process of English language. This is in line with the development of 21 st century lifelong learning that emphasises the diversity of teaching and learning methods leading to fostering four essential skills: critical thinking, creativity, collaboration, and communication to meet the country's aspirations to produce students who can compete on the world stage (Ministry of Higher Education Malaysia, 2018;Trilling & Fadel, 2009).
It is found that issues related to ESL students' poor performance in writing, especially argumentative essay writing and lack of critical thinking skills have been raised lately. Based on the previous studies, both ESL and EFL learners at the tertiary level often encounter problems in composing argumentative writing (Ariyanti & Rinda Fitriana, 2017;Maleerat Ka-kan-dee & Sarjit Kaur, 2015;Peloghitis, 2017). This problem is closely related to the lack of interesting and innovative pedagogy to learn writing. Students perceive argumentative essay writing as a rhetorically difficult, complex, and boring task due to the ineffective writing activities and modules used in the writing course and the method of instructions used in class (Botley, 2014;Vyncke, 2012). Nevertheless, in such a situation, students become apprehensive, disinterested in writing, and feel less compelled to put much effort into being critical when presented with an argumentative essay writing task. It has also been acknowledged by Yunus et al. (2006) and Chiew et al. (2016) that there is a lack of critical thinking skills among undergraduates in English language classrooms. This is further supported by Nabila Nejmaoui (2019) and Lu and Xie (2019) that there is a lack of empirical evidence regarding critical thinking in second language education. Thus, investigating ESL students' critical thinking performance in argumentative essay writing is considered crucial as the logical content consists of facts and solid information that requires students to generate their thoughts more critically to create new ideas and solutions related to argumentative topics.
It is undeniable that flipped learning approach has gained popularity among educators and its positive impacts on the students' learning process have created a space for researchers to explore the effectiveness of its implementation with the combination of peer instruction technique in argumentative essay writing. Thus, this study investigates the effect of peer instruction in a flipped learning environment on ESL students' argumentative essay writing.
Specifically, the research question for this study is: Is there any significant difference in mean scores for critical thinking in the posttest between the experimental groups (pair work, group work) and control group?

LITERATURE REVIEW
In general, the reviews are divided into three subsections: peer instruction in English language classrooms, flipped learning, and critical thinking cultivation in ESL/EFL writing.
PI is an active learning technique that allows students to articulate knowledge in their own terms and check their understanding by discussing it with other peers (Mazur, 2013;Schell & Butler, 2018;Zhang, Ding & Mazur, 2017). In addition, PI allows students to evaluate their thinking as well as exchange feedback from student-to-student, teacher-to-student, and student-to-teacher (Goodwin & Miller, 2013;Schell & Butler, 2018

Model of Argumentation (2003). The test scores for
pre-and post-tests were analysed and presented using descriptive and inferential statistics. Specifically, one-way ANOVA was performed to examine the differences between independent variables on one dependent variable at a time by using IBM SPSS Statistics 26 software. Therefore, students in the experimental groups received the treatments or interventions (peer instruction in a flipped learning environment), while students in the control group received the regular instruction (conventional teaching method).

RESULT
The research question set was, 'Is there any significant difference in mean scores for critical thinking in the posttest between the experimental groups (pair work, group work) and control group?' In testing the null hypothesis that corresponds to the research question in this study, data consisting of critical thinking scores of pretest and posttest from experimental and control groups were obtained. As the design employed was quasi-experimental with non-randomised samples, data were analysed using the analysis of variance (ANOVA) to explore the difference between the groups (and to test the null hypothesis). The pretest and posttest of the students' critical thinking scores was the dependent variable while the type of peer instruction (individual, pair work, and group work) was the independent variables.
Normality tests were conducted to determine if the data set was modelled for normal distribution.

A. Normality Assumption (Students' Critical Thinking Scores on Pretest)
In For the histogram (see Figure 1), the distribution frequency shows that data was normally distributed  Overall, the statistical analysis results showed that the data was normally distributed for the students' critical thinking scores on the pretest, thus parametric statistics technique, particularly, one-way analysis of variance (ANOVA) was used to compare means of two or more samples.

B. Normality Assumption (Students' Critical Thinking Scores on Posttest)
The descriptive statistics table (see Table 3) shows that the distribution of data for students' critical thinking scores on posttest was normal because both skewness (.051) and kurtosis (-.467) values were within the normal distribution range. For the histogram (see Figure 3), the distribution frequency showed that data was normally distributed because it displayed values clustering around the central peak with fewer instances further away. The stem-and-leaf distribution pattern in Figure 4 also clearly shows how the data was spread and that the distribution pattern was normal.   In short, the statistical results indicated that the posttest scores were normally distributed. Thus, this allowed the researcher to use one-way ANOVA to determine whether there were any statistically significant differences between the means of two or more samples.  In order to check the assumption whether the variance in pretest scores is the same for each of the three groups, a test of homogeneity of variances was carried out. other words, the equal variance assumption had been met and the null hypothesis was accepted. There was no significant difference between the groups for pretest scores. This was further confirmed with the ANOVA test results, as shown in Table 6. From the ANOVA results, it is noted that the F (2, 117) = .031, p = .970, ns, was not statistically significant at the .05 alpha level. Hence, it can be concluded that a one-way ANOVA showed that there was no significant difference between the three groups.

D. Equal Variance Checking and ANOVA Test (Students' Critical Thinking Scores on Posttest)
The descriptive table (see Table 7 (Barahal, 2008;Beaumont, 2010). Apart from the in-class activities, critical thinking was also promoted through the flipped classroom before entering the class as students had to pause videos to think about the learning content and then summarise the main points in the lesson study logs (Hamdan et al., 2013;Herreid & Schiller, 2013). Through the present study, it is confirmed that argumentbased writing is an optimal way to train university students' critical thinking as it helped them analyse and evaluate different types of evidence and stances Furthermore, the finding also proves that cognitivism has significant contributions to integrating peer instruction (pair work and group work) in a flipped learning environment. In line with Piaget's emphasis on knowledge construction by learners based on their existing cognitive structures (Piaget, 1952), students in this study were trained not about what they could do but instead what they know and how they came to learn that information.
For instance, students engaged themselves in class discussions related to argumentative essay topics and tasks whereby they had to provide opinions based on their prior knowledge, exchange their ideas with other group members and organise their thoughts logically.
Apart from that, providing the right environment and task requirements is also considered as the key importance in developing students' critical thinking such as making claims, counterclaims, and rebuttals, as well as using clear reasons and evidence to both substantiate and refute the opposing argument.
Therefore, through the process of peer instruction in a flipped classroom environment, students were able to immerse themselves in a fun, challenging (argumentative essay writing) and safe learning environment.
Despite a significant result in the ANOVA, post-hoc pairwise multiple comparisons using the Bonferroni's test revealed that comparisons between students' critical thinking scores in experimental (pair work) and the experimental (group work) were not statistically significant. This could be due to the fact that students in both groups experienced similar procedures in learning the primary course content outside of the class and spending class time working in pairs or groups to apply that content. In short, the empirical result of this present study strongly suggests that the peer instruction in a flipped learning environment involving pair work and group work modes should be considered as a combination of two pedagogical approaches in enhancing ESL students' critical thinking scores in argumentative essay writing.

CONCLUSION
The result of this study showed that the use of peer instruction in a flipped learning environment (pair work and group work) has effectively enhanced the ESL students' critical thinking performance in argumentative essay writing. This positive effect implies that English language instructors have a potentially useful instructional strategy in guiding ESL students to be critical thinkers when practicing the language by making cases in argumentative essay writing.
Thus, it is suggested that teachers should consider applying this combination of instructional strategy and teaching approach as an additional option for enhancing writing instruction and also add to their repertoire of current teaching strategies that cater to argumentative writing. The English teachers need to plan, manage, support, and assist the students' learning process by engaging them in various learning activities and boosting their critical thinking skills. In other words, English teachers need to make the necessary changes to the teaching and learning process of argumentative essay writing.
Indeed, applying various teaching methods and techniques can increase the students' ability to think critically.