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The effect of blended learning setting on students’ critical thinking skills in physics

This paper reports a study and results of the improvement of critical thinking skills in a blended learning environment in teaching high school physics. The research was a mixed-method quasi-experimental followed by a qualitative survey. Schoology is chosen as a blended platform for this study. The data of students’ critical thinking skills were obtained by multiple choice tests and were analyzed by using n-gain. Moreover, the information on students’ responses to the blended learning model was collected by open-ended questions at the end of learning process. Based on the results of the study, there were significant effects of blended learning on critical thinking skills. It is also reported that students have high interest, ease of learning, and have benefits in increasing their knowledge. It suggests that Schoology-based blended learning model is effective to improve students’ critical thinking in Physics learning process.


Introduction
Triggering learners to develop their critical thinking ability is taking a significant issue now days. In regard to ever-changing and challenging current digital age, teachers and educational stake holders have to prepare and develop their learners to enable thinking critically and making a strong decision as necessary competence in social problem in rapidly changing world [1,2]. Critical thinking skill is also needed to foster students' thinking skill since it requires examining assumptions, discerning hidden values, evaluating evidence, and assessing conclusions. Furthermore, thinking critically also develop other skills, such as higher concentration levels, deeper analytical skills, and focusing problems [2].
Currently, literatures have defined critical thinking as the important skill in order to succeed since it engage learners learn in both professional and personal learning process [3]. In the same side, Saadé et al. [4] argue that critical thinking enables ones to differ between personals and logical reason as making it to be important and hard to achieve. Moreover, it also has special importance in making a decision and judgment which take them into their career. Lee has also supported by arguing that critical thinking is crucially needed in changing technology age since it is closely to the gap between skill and knowledge needed in workplace [5].
Considering to the dramatic IT used for teaching and learning, it suggest creating and exploits endless learning opportunities. Some researchers argue that giving opportunities by integrating technology in science learning can achieve more active engagement and higher quality than conventional one [6,7].
The ICT usage is also reported that it affects to foster critical thinking skill and changes its usage [4,8,9,10]. In line with a study by Bester and Brand [11], ICT-based teaching and learning is also claimed that it can foster cognitive, creativity and critical think skill. Furthermore, another study has also proved that information technology enable to foster students more active and critical in thinking [4].
Since the online learning has several problems dealing with it implementation, scholars and stake holder have tried to explore another cooperative learning approach named blended learning. Literatures report that researchers have explores various platform in the blended learning in teaching learning such as integrating WhatApp based blended class [9,12,13]. It is also mentioned that WhatApp is the most preferenced used as mobile integrated learning since it is free to download, easy to use, simple, asseseble, low cost, and also multifunction [12,13]. Some other studies also claimed that this platform give a lot of opportunities to create positive environment, motivate students be more active, easily to communicate and give positive feedback [13,14,15].
Nevertheless, some studies have also revealed that this platform cannot be easily applied in the class [16,17,18]. In other literature, Amry in his study of blended learning using Whatsapp suggests that the strategy give more negative impact than its positive impact on students' performance [17]. One of possible reason might be because of its limitations on textual resources of academic conceptualization and unsure within the academic grip of the discussion result using text messages in this application [18]. Then, both teachers and students more prefer to use it for interaction and others purposes than to education [16].
Thus, it remained great interest to explore other kinds of platform used in blended based learning especially for sustaining Physics teaching learning process. In addition, the limitations of the literature regarding the effect of blended learning in students critical thinking especially in Physics field in Lampung, Indonesia, are such a reason for conducting this research. Therefore, it is urge to do further investigation due to this matter. The purpose of this study were to examine the effectiveness of blended learning setting using Schoology in improving students' critical thinking and to explore students' response about the learning approach.

Method
The study was conducted in order to explore the effectiveness of blended learning setting to support students critical thinking skills and also their perception through the process. This research was done in one of senior high school in Metro, Lampung, in odd semester of 2018/2019 academic year with 65 students in total, 32 students for experiment group and 33 students for control group. The present study carried mixed-method, a quasi-experimental followed by a qualitative survey in order to meet the objectives of the research. There were two stage in collecting the data namely quantitative stage and qualitative stage. In quantitative stage, the quasi experimental is adopted during the process. Before giving treatment, both experimental and control groups were given pre-test. In the experimental group, learning was done with Schoology-based blended learning system with a guided inquiry learning model. Blended learning used has a cycle of online face-to-face learning-online learning, referring to previous studies [19]. The number of face-to-face meetings in both classes is four meetings with duration of 90 minutes for each meeting. Meanwhile, control class only received conventional treatment. The end of the first stage, the post test was conducted in order to get information about students' critical thinking skill.
For collecting the quantitative data, multiple choice tests was used in term of critical thinking skill. The test included five indicators of critical thinking namely focusing questions, analyzing arguments, considering trusted sources, identifying assumptions and determining actions. Data taken from both pretest and post-test is useful to identify the differences of students' critical thinking skills. The test used in this study has been tested for its validity with Person Correlation >0.1954 tested at 70 students. Furthermore, regarding its reliability, the cronbach's alpha method was used and got the valued at 0.876. Furthermore, in order to get better understanding about the issue, the second stage was done by conduction survey. In collecting qualitative data, the survey was done in order to getting better understanding of students' perception on blended learning process. A survey was conducted in the researcher's class consisting of 32 learners via a questionnaire. The instrument used for this study was a structured questionnaire to identify if the factors such as peer interaction, tutor support, online task, technology support, and knowledge acquired influence respondents satisfaction in the collaborative online learning assignment discussion; and to determine factors that are most indicative for learner satisfaction in a collaborative online discussion forum.
Since the study has two types of data namely quantitative and qualitative data, the researchers used two kinds of data analysis techniques. For analyzing data of quantitative, the statistical analysis of SPSS 21.00 which has 0.05 significant levels is used in this study. For having deepest understanding of the implementation, the descriptive qualitative was used to analyze the questionnaires. The results obtained from the questionnaires are in the form of percentage of students answers detailed on each question. Through this information, we can find out the effectiveness of learning using blended learning platform.

Result
In experimental stage, online-face to face-online learning was done with guided inquiry based learning adopted the blended learning proposed by Suana et al. [19]. In online platform, the students tried to have discussion related the topic before the class. From the online discussion, it is found that most of learners are having more confident in expressing their ideas.
Moreover, both experiment and control classes have received pre-test and post-test. The data obtained from those tests related to critical thinking skill are presented in Table 1. The five indicators contained in the question of critical thinking ability obtained data that were not normally distributed and homogeneous so that the Mann Whitney U-Test Test was used which can be read in Table 3. Based on Table 2 and Table 3 if the value of Asymp. Sig. (2-tailed) < 0.05) It can be concluded that H0 is rejected. Based on the results of the test, it can be obtained that there is a significant difference in the critical thinking ability of the experimental class students and the control class. These data indicated that the indicators focused the questions, determined the sources to be trusted or not, identified assumptions and determined actions in which there were differences in students' critical thinking skills in the experimental class and the control class. Meanwhile, for the indicators in analyzing the arguments, there were no differences in the two classes. In short, the blended learning plat form is carried out an influence of students' critical thinking skills in the experimental class.

Tabel 3. Statistics test Mann Whitney U-Test
In second stage, a questionnaire regarding students 'responses to blended learning was given, which was related to students' attractiveness regarding learning the blended learning model, ease of participating in blended learning, the benefits of participating in blended learning, and constraints in following blended learning. Based on the results of the questionnaire that has been given to students, after doing blended learning has been drawn in Table 4. Based on the questionnaire it was obtained that attractiveness following blended learning students in one class more than 2/3 of the students. The ease of use of blended learning is found as the reason why students are interesting in blended learning. From the study, It is revealed that more than 80% students have felt blended learning easy to use and flexible due to time and place. The benefits of blended learning are almost 80% useful but have high obstacles for all students on internet connection problems. From the open ended questions, it is also found that blended learning suggests enriching students' learning experience.

Discussion
Mixed learning between face-to-face and online learning using guided inquiry methods further enhances students' critical thinking skills rather than conventional learning. This is in line with the results of research conducted by Zain that physics learning using guided inquiry models based on blended learning further enhances students 'critical thinking abilities [2]. This present finding is also similar with previous findings which claimed that ICT-based learning can foster critical thinking skill [11,8,9,4,10]. The other previous study has also proven that Schoology serves to conduct exercises and tests, provide learning content such as showing articles, videos or simulations and for collaborative activities such as discussion groups (Picaino, 2017). Online learning is carried out in this learning by giving a problem then students discuss the problem to give a hypothesis. Through this can improve the ability to think critically with indicators focusing questions and analyzing arguments. After that, doing face-to-face learning with an experimental method that starts with collecting data, analyzing data to draw conclusions so that it can develop critical thinking skills with indicators of critical thinking considering sources can be trusted or not, determine assumptions and determine actions. After that, at the last stage, online learning that is used to conduct discussions can make students' critical thinking abilities increase with indicators determining actions. Similar to the research conducted by Agnan (2018) through the method of argument analysis can improve critical thinking skills because through argument students will develop logic to provide these answers.
Based on the results of questionnaire give to students, it is revealed that many students were interested in learning using Blended learning through Schoology. The possible reasons are the learning system is easy to use and also increase the learners' motivation. This finding is similar with the previous study which claimed that blended learning has increased student motivation [20] (Barbour & Reeves, 2009). Moreover, through this learning platform, learners can also have new learning experience. This result is simiar with study by Cooner which suggests that blended based learning claimed to improve students' learning experience [21]. By using this platform, from open ended questionnaire, students argue that they are interesting because learning process can be done anywhere and anytime. Pratt and Trewern