Students' Creative Thinking Skills on Reaction Rate Topic through Contextual Teaching and Learning Model

This research aims to analyze the contextual teaching and learning (CTL) model on students' creative thinking skills on the reaction rate topic. This quantitative research used true experimental design of pretest posttest control. The samples used in this study were from 11 th grade at SMA Negeri 1 Pinolosian. The experimental class sample was given treatment of the CTL learning model while the control class used conventional learning, respectively, were 31 and 30 students of 93 populations. Based on a questionnaire, students' creative thinking skills were obtained through observation during the learning process. The data analysis of the test instrument was carried out through a validity test using the product-moment correlation technique (significant level = 0.05), Lilliefors normality test, homogeneity of variance test and t test . The CTL implementation questionnaire and instrument test data were converted into percentages and categorized. The results showed that the application of the CTL model had a positive effect on students' creative thinking abilities, evidenced by the average score of students in the experimental class before and after treatment increased from 14.55 to 74.84. Otherwise, in the control class, the scores were 30.59 to 33.56. The percentage of students' achievement in creative thinking aspects in the experimental class was good (61%-80%) while the control class was less good (21%-40%). The creative thinking abilities of both classes are very different, which is also reflected in the learning outcomes. The value of t count (2.240) was greater than t table (2.042) at the significant level = 0.05, and the hypothesis of H 0 was rejected, or H 1 was accepted. The application of the CTL learning model positively influenced students' creative thinking skills on the reaction rate material. Students' low originality abilities compared to fluency, flexibility, and elaboration abilities were also discussed.


Introduction
The standard of 21 st century education is to have creative thinking skills. Every teacher plays an important role in achieving an educational goal. One of the main goals of this century's education is to emphasize students' ability to think creatively. Creative thinking is an activity to solve a problem that is carried out through an unconscious experiential process which includes fluency in generating a number of ideas, flexibility in using time in producing various types of solutions obtained, novelty of ideas or solutions produced (Coon Jurnal Tadris Kimiya 7, 1 (June 2022): 147-156 This is an open-access article under CC-BY-SA license (https://creativecommons.org/licenses/by-sa/4.0/) Students' Creative Thinking Skills on Reaction Rate Topic through Contextual Teaching and Learning Model & Mitterer, 2014). In the 2013 curriculum, the learning process is expected to encourage students to be able to ask questions, reason, and explain the subject matter that has been obtained so that the learning process is more meaningful (Syuhada et al., 2020, Osman et al., 2015. Creative thinking is the ability to develop an unusual discovery of new ideas, as well as quality of ideas (Febrianti et al., 2016) . The ability to think creatively is also a person's process of thinking and expressing new relationships, seeing events from a new perspective, and being able to combine two new concepts that were previously known (Putra et al., 2016). Students must have the ability to acquire, choose, criticize, be systematic, be logical, be creative and the ability to work together effectively (Samosir et al., 2019). The creative thinking process is convergent to capture the situation, make evaluations and consider the consequences of the chosen solution (Winarti, 2016;Daud et al., 2012).
One of the suitable learning models for the 2013 curriculum and in accordance with authentic assessment is Contextual Teaching and Learning (CTL) (Juniwati & Sari, 2015). This learning model can help teachers relate the material being taught to students' real world situations and encourage students to be able to connect their knowledge with its application in everyday life (Ariesta et al., 2013). In delivering the material, the selected context or example must be in accordance with the daily life and cognitive level of students. Therefore, the selection of appropriate examples can help students to think and take responsibility for their ideas or opinions. Students become more actively involved in discussions so that they are more confident in expressing their opinions and asking questions about things related to the material being studied (Artini et al., 2019) .
The CTL model can improve student learning outcomes because students work and experience, not just receiving material from the teacher (Addaini & Alvina, 2020) . This model can also build conducive interactions between students and teachers (Suryono, 2019) and motivate students to understand the meaning of each material through connectivity with everyday life (Zhafirah & Utami, 2019;Yamin, 2013). These activities indirectly affect students' ability to think critically and creatively in solving various problems they experience (Putra et al., 2016). This model can make students more active in learning, asking more questions, and following learning well (Saputra et al., 2020).
The results of the initial observation at the Senior High School in Bolaang Mongondow Selatan showed that not all of the basic chemistry competencies for 11 th grade was taught to students. The teacher only chooses basic competencies related to material at an advanced level and phenomena can be found by students in everyday life. The learning is carried out from home because of the Covid-19 pandemic. Students tend to learn by memorizing, not understanding, and there are many students who feel bored. La Kilo (2017) reported that many students do not understand chemistry because their tendency is to memorize without understanding. This way of memorizing has a bad effect on students' creative thinking skills in processing information from chemistry subject which has an abstract concept. Reaction rate is one of chemistry materials that is abstract and difficult for students to understand (Taofek & Agustini, 2020) . The learning process that takes place in schools is still oriented to the teacher who delivers the material, while students only act as recipients of information (Siswanto & Mustofa, 2012) .
This study aims to study CTL model on students' creative thinking skills of the reaction rate topic. The creative thinking abilities of students studied consist of four aspects, namely fluency, flexibility, originality, and elaboration.

Research Method
This research was conducted at SMA Negeri 1 Pinolosian (Pinolosian Public High School 1) on second-grade of science students 2 and science students 3, respectively, as the experimental class (31 students) and the control class (30 students). The samples were taken from 93 populations (three classes) by simple random sampling. The CTL model was applied in the experimental class for three meetings (2 x 45 minutes per meeting) while the control class applied a conventional model. The main stages of the CTL model are observing, asking questions, collecting and communicating the topic given. Students observed the phenomenon of swimming pools that were given chlorine. The teacher involved students in asking questions and seeking information on the topic. Data collection was based on student worksheets regarding factors affecting the reaction rate. In groups, students read and discuss/analyze the questions and then provide conclusions from the given phenomena. The next stage (association), students conclude the factors that affect the reaction rate. Each group conveys and concludes the results of joint discussions regarding the phenomena that have been presented in the worksheet. Finally, students pay attention to the teacher's explanation of the factors that affect the rate of reaction.
The research design used pretest-posttest control. The data for the two classes were collected using questionnaire and test. The questionnaire used was intended to determine student responses to the use of the CTL model on the reaction rate topic (Table 1). Students' creative thinking skills were obtained through a written test instrument with nine items of reaction rate material. This instrument refers to the four indicators of students' creative thinking aspects proposed by (Purwaningrum, 2016); fluency, flexibility, originality, and elaboration.

Table 1. Questionnaire on the Implementation of the CTL Model Code
Statements S1 The teacher conveys the learning objectives well S2 Each case given by the teacher in learning the material on the rate of reaction can be done either individually or in groups. S3 I can cooperate better with a group of friends when working on tasks related to everyday life. S4 The understanding of the reaction rate material becomes better after the teacher explains the material related to everyday life. S5 The results of my study of the reaction rate material increased. S6 The atmosphere in the classroom is more conducive and fun when the teacher explains the reaction rate material associated with everyday life. S7 The presentation of the questions displayed relating to daily life described by the teacher, adds to the understanding. S8 After explaining the reaction rate material associated with daily life, I became bold in communicating with my friends and teacher during the learning process. S9 The explanation of the reaction rate material associated with daily life presented by the teacher may increase my desire to explore the material, especially the reaction rate material. S10 I think that the CTL method applied by the teacher in the classroom, especially in learning the reaction rate material is very appropriate.
In this study, the measurement of students' creative thinking skills used a written test instrument. The instrument refers to four indicators of the creative thinking aspect of students proposed by (Purwaningrum, 2016).
The criteria for assessing students' creative thinking abilities can be seen in Table 2.
Students' Creative Thinking Skills on Reaction Rate Topic through Contextual Teaching and Learning Model Analysis of observational data was carried out by observing students' creative thinking skills during the learning process. Then the data were analyzed and described to determine the effect of the CTL model. Meanwhile, the data analysis of the test instrument was carried out through a validity test using the product moment correlation technique (significant level = 0.05), Lilliefors normality test, homogeneity of variance test and t test . Data of the CTL implementation questionnaire and instrument test were converted into percent and categorized by score as shown in Table 3.

Implementation of the CTL model
The use of the CTL model on the reaction rate material obtained a very good response from most students as the results of the questionnaire shown in S1, S3, S4, S7, and S10 in Figure 1. Students were able to work well with the tasks given by the teacher. The teacher conveyed learning objectives well and presented the material in an interesting way, which was related to everyday life. In addition, the curiosity and communication arising from the students resulted a conducive classroom atmosphere as well as the support for presentations from S2, S5, S6, S8, and S9. There were a small number of students who responded negatively to this CTL model, especially cooperation (S3) and curiosity (S9). The CTL model applied to this reaction rate material has met the requirements and the data obtained can be used in this study as well as the results can be compared with conventional learning.  Nugraheni (2015) reported that the CTL model can make students care about the environment compared to conventional learning. This research not only made students care about the environment but students also care about learning as expressed in the passion and cooperation between students.

Test Data 3.2.1. Normality
The normality test in this study used the Liliefors formula with a significant level of 0.05. The results obtained from the two classes can be seen in Table 4. The results of the normality test of the pretest and posttest for the experimental class (second-grade of science students 2) and the control class (second-grade of science students 3) showed that the L table at the significant level of 0.05 was 0.242. This score was greater than the score of L count (L count < L table ) so that H o was accepted, the data were normally distributed.

Homogeneity
The homogeneity test used Fisher (F) test with a significant level of = 0.05. The results of the homogeneity test obtained from the two classes can be seen in Table 5. The data showed that the F count < F table (1.091 < 1.854) so H 0 was accepted which indicated that the variance of the two samples was homogeneous.

Hypothesis
The results of the calculation of the normality test and the homogeneity of variance at the pretest and posttest showed that the two samples (classes) were normally distributed and homogeneous, so that the hypothesis testing requirements in this study were met with the t test . H as the results of the calculation obtained the value of t count = 2.240 and t table = 2.042 with a significant level of = 0.05. Because t count > t table , then H 0 was rejected or H 1 was accepted. This means that the application of the CTL model has a positive influence on students' creative thinking skills on the reaction rate topic.

Students' Creative Thinking Skills
The achievement of creative thinking skills of experimental class and control class students were shown in Figure 2. The results of the control class students' creative thinking were very low for all indicators, with an average score of 30.7%. Otherwise, the creative thinking ability of experimental class students who were taught using the CTL model was high, with an average score of 73.70%. Specifically, for the experimental class, three students scored in the high category (85), 20 students in the medium category (between 70 and 85), and eight students scored low, 70. Students' Creative Thinking Skills on Reaction Rate Topic through Contextual Teaching and Learning Model always think of more than one answer, with an ability level of 76.77%. In the second aspect, flexibility skill got score of 76.40%, meaning that students are able to generate ideas, answers or can look for many different problem-solving alternatives. Creative thinking are also a habit of a person to turn on an imagination, express and create amazing new points of view and unexpected ideas (Purwaningrum, 2016) . The elaboration skill of students was 76.45% which means students can enrich and develop ideas that lay out the details of a situation so that it is more interesting. Meanwhile, students' originality skill decreased to 65.16% compared to the other three thinking skills. The achievement in the originality aspect was low compared to the fluency, flexibility, and elaboration thinking aspects. In the control class, the ability to think creatively from fluency, flexibility, originality, and elaboration was successively 29.3%, 31.5%, 20%, and 42%. Pikoli et al. (2022) reported that students' multiple representations in understanding the concept of reaction rate were still very low at the submicroscopic level namely the three mental models from the initial, synthetic, and scientific models were 36.2, 29.4 and 34.4%, respectively. Even the type of mental model (both answer and reason were wrong) was found in many students in determining the graph of the relationship between the rate and the concentration of the reactants (Setiawati, 2020). It shows that conventional learning on the reaction rate material is not able to explore students' creative thinking skills. Conventional learning encourages students to only memorize instead of understanding which can cause students to lack understanding of chemistry because the creativity potential of students does not rise (Hasanah et al., 2020;Laliyo et al., 2020;Subawa et al., 2018). The inquiry learning model and scientific approach are effective in improving students' critical thinking skills on the reaction rate material (Agustin et al., 2016;Ilaah, 2015).
Students' thinking ability was also reflected in the pretest and posttest outcomes on topic of factors affecting the rate of reaction as shown in Figure 3.

Figure 3. Average of Pretest and Posttest for Experimental and Control Class
Based on Figure 3, the pretest results of the experimental class obtained an average of 14.55% which was lower than the average score of the control class 30.59%. In contrast, the posttest results of experimental class after the implementation of the CTL model increased with an average score of 78.84%. This means that the creative thinking level of the experimental class students to complete and answer the questions has reached the minimum completeness criteria (Kriteria  (Jumi et al., 2018). One aspect that is predicted to increase the ability of originality is to guide students intensely in solving problems. Through the guidance process with a science process skills approach, students are directly involved, not only listening, but they also can solve problems in the laboratory to gain knowledge (Ischak et al., 2020) . Here students really act as scientists in discovering new ideas. Hasanah et al. (2020) also reported that students' innovations or new ideas in solving chemical problems related to everyday life can be improved through the STEM-Cp (Science, Technology, Engineering, Mathematics, and Contextual Problem) approach. Students' independence in learning to practice creative thinking skills can be done through STEM-Cp-based books that are associated with problems in everyday life (Hasanah et al., 2020).

Conclusion
The application of the CTL model positively affects students' creative thinking skills on the reaction rate material. On the other hand, conventional learning does not generate these abilities. This was proven through statistical analysis of test results from pretest and posttest. Through CTL learning, students' creative thinking ability was high (73.70%), although the score of originality ability was lower, 65.16%. To train students' thinking skills, especially originality, it is estimated that this can be done by self-study through the STME-Cp-based reaction rate book and guided learning with a process skills approach.