Developing Guided Discovery Learning-Based Neurodroid Learning Media for Critical Thinking Skills

_______________________ *Correspondence Address: amelialestari2@gmail.com Abstract: This study aimed to develop guided discovery learningbased android learning media to improve critical thinking skills. The developed biology learning media was applied to the nervous system material. The discussion of the physiology of the nervous system is one of the difficult biological materials to understand because it includes the organization and structure of neurons and their functions, ion pump mechanisms when neurons are at rest, action potential mechanisms, mechanisms for neurons to communicate with other cells in the synapses, and organization of the nervous system. This study used research and development (R&D) with a method developed by Thiagarajan, namely the 4D model with stages: define, design, develop and disseminate. The stages of this study are limited to the development stage. The results showed that the media was feasible with media, language, and a material expert validation of 3.5, 3.8, and 3.3, respectively.


INTRODUCTION
The student's difficulties in learning biology have been studied by various researchers worldwide. Some topics in biology that are considered difficult for students to study are water transportation in plants, protein synthesis, photosynthesis and respiration, gas exchange, energy, cells, mitosis and meiosis, organs, physiological processes, hormone regulation, oxygen transport, genetics, Mendel, genetic engineering, and the central nervous system (Çimer, 2012;Tekkaya et al., 2001).
Biological sciences such as the nervous system include detailed and abstract concepts of biological organization level (Çimer, 2012;Tekkaya et al., 2001); plus an overloaded biology learning curriculum, interdisciplinary biology concepts, and the limitations of textbooks in presenting and explaining biological concepts Zeidan (2010); Osborne & Collins (2001). The nature of biological science, biology learning is generally based on rote learning, which includes many concepts, events, topics, and abstract facts, making it difficult for students to learn them (Bulent, 2015;Durmaz, 2016). No less important factors are the teacher's teaching style, biology teaching methods, and the use of learning media (Çimer, 2004;Etobro & Fabinu, 2017).
The actualization of biological sciences in life is needed to respond to the changes and new challenges in the 21stcentury (Zabit, 2010). This shows that in biology learning, it is not only the ability to memorize concepts, events, and facts of biology, but students need critical thinking skills to answer the challenges of the 21st century. This is following Makaramani (2015) explanation that in 21st century learning that the learning process is not only contained subject matter, but every student needs to know how to use their knowledge and skills by thinking critically, applying knowledge to new situations, analyzing information, understanding new ideas, communicating, collaborating, solving problems, and making decisions.
Students' critical thinking skills can help overcome problems or challenges by considering various perspectives, understanding and organizing important facts of situations, and designing appropriate solutions (Facione, 2000). Critical thinking is a detailed description that includes the process of interpretation, analysis, evaluation, inference, explanation, and self-regulation (Facione, 2015). Critical thinking is also defined as an attitude of wanting to think deeply about problems and things that are within reach of one's experience, knowledge of methods, and logical reasoning and skills to apply these methods (Glaser in Fisher, 2003). The critical thinking skills possessed by students can facilitate the completion of the implementation of tasks and the process, help make their conclusions, and actualize knowledge in life (Zabit, 2010). Critical thinkers in learning activities use reflective decisionmaking and problem solving to analyze situations, evaluate arguments, and draw appropriate conclusions on the concept of learning material (Shehab & Nussbaum, 2015).
Through a pattern of activity, independence, and student curiosity in learning with teacher guidance, Guided Discovery Learning (GDL) is more effective than conventional models because it increases students cognitive understanding integrally (Khasanah et al., 2018;Yuliana et al., 2017). Compared to pure discovery learning with guided discovery, learning is more meaningful (Alfieri et al., 2011;Mayer, 2004). Guided discovery learning refers to the pattern of scientific methods so that students can find problem-solving by students in groups with the steps of stimulating, formulating problems/identification, collecting various data sources, performing data processing, confirming or re-check data sources, and the final stage is drawing conclusions (Akinbobola & Ado, 2007;Deswita et al., 2018;Novita et al., 2016). The benefits of GDL are to positively impact students, such as critical thinking, creativity, making decisions problem solving and motivated in learning through active (Akinyemi Olufunminiyi Akinbobola & Afolabi, 2010;Omwirhiren, 2002).
Media use in 21st-century learning is closely related to information technology as supporting material for educators in developing learning media and refers to students' critical thinking (Hidayat et al., 2019;Puspitasari et al., 2018). Technological development is one alternative for effective, efficient, and superior learning media. Therefore, android-based learning is effectively used as a learning medium in the 21st century (Yusuf, Widyaningsih, & Purwati, 2015).
Utilizing technology in instructional media greatly helps improve problemsolving abilities and learning outcomes (Astutia et al., 2017). One use of technology in learning is learning with cellular. The use of cellular as a learning medium has a better and more effective impact and can enrich experiences in the learning process of students (Fulantelli et al., 2014;García-Peñalvo & Conde, 2015) (Adnan & Prasetyo, 2017. Mobile learning provides various application programs that students can access, for example, Android programs (Abildinovaa et al., 2016).
Android can be the right learning media, especially for high school students, because almost every student sees it as an object of activity and interaction with a duration that is often used (Mardiana & Kuswanto, 2017). Android can also help students access information at any time as needed (Ligi & Raja, 2017). Tania & Jumadi (2020) also adds that androids can enhance learning in various ways and contexts. Potential and existing problems, this research focuses on the development of learning media based on a combination of the android nervous system and guided discovery learning on its effect on critical thinking skills.

METHOD
This research and development study aims to develop learning media for android-based nervous system material (Neurodroid). This study uses research and development (R&D) with the method developed by Thiagarajan et al., (1974) of 4D model stages (define, design, develop, and disseminate). The initial step in this research model starts from the define stage, which is to determine the needs needed by students in studying the nervous system. At this stage, several things must be analyzed, starting from analyzing student needs, concept analysis, task analysis, and formulation of learning objectives. All that is done in the first stage is to define aims to provide an overview and determine the type of media to be created.
The second step is designing, starting from making a storyboard, describing the concept of the material and determining the images and videos that will be included in the Neurodroid media, and compiling instruments to measure students' critical thinking skills that are separate from Neurodroid media but are an integral part of the research. Neurodroid media is made using the android studio 3.6.3 application.
Next is the development stage, which is developing respiradroid media, to produce development products at this stage, carried out through two steps, namely: (1) expert assessment in the field, followed by revisions, (2) developmental testing (developmental testing) the goal is to retrieve data for media validation from students. Two material experts and two media experts conduct product viability testing. Data analysis uses a mean score which is then converted to a standard value in the form of a percentage of feasibility.
The final stage is dissemination. The media that have been developed will then be used by other students and disseminated.
The sample of this study was students of class XI MIA of SMAN 48 Jakarta, with 76 students. The research design carried out in this study was using Quasi-Experimental Design. This can control all external variables that affect the course of the experiment. Test the validity of the study using the Point Biserial correlation formula using the following formula: (Arikunto, 2012)

RESULT AND DISCUSSION
The descriptive analysis and hypothesis testing showed that guided discovery learning-based Neurodroid media had a significant effect on students' critical thinking skills. Students taught using guided discovery learning-based Neurodroid media were higher than students taught using conventional learning.
The reactions obtained from this stage are from assessment results from judgment experts, namely media and material experts. The validation results ensure good qualifications based on the assessment given by experts with an average value of 3.5, meaning that the Neurodroid media developed is valid (Table 2). The next assessment criteria (Table  3.), namely aspects of implementation and interface, contain items presenting Neurodroid media's implementation, appearance, display design, and image format and media resolution of Neurodroid media. Based on the validation results from the experts, they stated that the implementation and interface aspects were valid with a result of 3.08, which means that the Neurodroid media was valid. The suitability of the format and resolution is displayed by considering the choice of colors and a soft display to not interfere with students' vision and comfort when learning. In Table 5, it can be explained that before applying guided discovery learning-based Neurodroid media, the average achievement of students in critical thinking skills was 51.48 in the experimental class and 51.84 in the control class. These results indicate that none of the students achieved the KKM score of 75, both in the experimental and control classes. Based on Table 6, the highest score in the experimental class is on the interpretation indicator, namely 96.38, while the lowest value is in the explanation indicator, which is 77.30. After learning with guided discovery learning-based Neurodroid media, students can interpret, analyze, conclude, evaluate, explain the nervous system material both on the aspects of the nerve cell parts and their functions, the principle of impulse delivery, the mechanism of movement, and reflex motion, the nervous system structure and disorders of the nervous system. However, if viewed from the increase in the value of the pretest to the post-test, the self-regulation indicator was the indicator that experienced the largest increase, with a difference of 41.11, which initially scored 45.07 to 86.18. At the same time, the indicator with the lowest increase is the interpretation indicator with a difference of 20.06, which initially scored 76.32 to 96.38. These data indicate that guided discovery learning-based Neurodroid media can improve critical thinking skills. This is in line with Aprelianda & Yerimadesi The guided discovery model is deliberately designed to increase students' activeness, is process-oriented, and students can find and have their information needed to achieve learning goals (Yuliani, 2015). Learning activities like this make students active in the learning process. The teacher only acts as a facilitator to organize the course of learning. The learning process has a positive impact on the development of students' critical thinking, helps students develop intellectual discipline, the need for skills arouses curiosity, and seeks answers to curiosity. In addition, guided discovery learning can encourage students to think for themselves and analyze themselves to find general principles based on the material or data provided by the teacher. Students are trained to build thinking skills that focus on understanding in the guided discovery model. This is similarly expressed by Risdianto et al., (2013). The purpose of guided discovery learning is to provide a way for students to develop intellectual abilities (thinking skills) related to reflective thinking processes.
The results of this study indicate that the guided discovery learning model is more suitable with the characteristics of high school students because to support the application of the guided discovery model in the learning process, the teacher as a facilitator needs to provide learning media, such as modules to help students learn both independently and in groups. This statement is supported by Udo (2010), and Akinbobola & Afolabi (2010) that guided discovery is most effective for student-centered learning and facilitates student learning outcomes. This is because what is meant by the discovery in guided discovery is not finding something completely new. Still, in this model, students are expected to actively find knowledge such as guessing, estimating, and trying to find concepts, formulas, and the like. Students find the concept through guidance and direction from the teacher because, in general, most students still need basic concepts to find something.
Guided discovery is very useful for learning the nervous system using media following abstract biological characteristics. This aligns with Sugiyono (2017), arguing that guided discovery is learning using discovery. Students gain knowledge to be understood with teacher guidance, such as through questions, demonstrations, or other media. Likewise, according to Markaban (2006), the guided discovery syntax is (1) the teacher formulates problems that will be given to students with data according to the topic of discussion; (2) students look for, process, compile, and analyze data; (3) students make conjectures (predictions) from the results of the analysis carried out; (4) then the hypothesis made by the students is examined by the teacher; (5) verbal presentation or presentation is also carried out by students to be discussed, processed and confirmed together; (6) After students find what they need, the teacher provides additional exercises or questions to check whether the findings are correct. From the description above, it can be concluded that guided discovery is a learning model that presents a problem or question that allows students to think, observe, make guesses, explain, and analyze to find guidance and instruction from the teacher.
In the control class with the application of conventional learning, critical thinking skills were lower (Table  3) than the experimental class that applied guided discovery with Neurodroid media. The value of students has increased, but it is still low in some aspects. Such as the analysis and explanation aspects, which only score 71% each. This is because the discussion process has not been optimal and has not generated curious problems to be solved. It has not been able to properly analyze and evaluate neuron system material. This is also due to the absence of a component to formulate problems and determine hypotheses in the student worksheet. Learning focuses on the discussion between groups that are not directed so that students are less motivated in critical thinking. This can be seen during the presentation. Some group members who appeared chose to be silent and relied more on the group leader to present and answer questions from other group members.
In the control class, facilitators' teachers do not contribute less to the learning process. The teacher only provides direction at the beginning and the initial activities. This causes students to take important points from the book to be presented. Group members also did not understand what they were presenting. Several groups were still wrong in compiling the concepts presented. This is not right because wrong concepts have been formed in students' memory before any improvement or validation from the teacher.
The group that appeared was also unable to answer the other groups' questions. This shows that the management of the discussion is not good, especially at the planning stage, which causes the implementation stage not to go well, which impacts the achievement of learning targets. According to Gupta & Ahuja (2014) and Espey et al. (2017), teachers as facilitators must encourage students to initiate discussions and ask questions for clarification. Furthermore, Jarmita (2012) added that in group discussions, teachers must also assist in finding answers with the flow of thought of each student.
The calculation of critical thinking skills results shows normal and homogeneous data. The correlation test shows that the pretest is significantly correlated with the post-test, so the ANOVA test is needed to determine whether the pretest affects the post-test. Without the pretest value, there is an effect of using guided discovery and conventional Neurodroid media on the post-test scores of critical thinking skills, which means that the post-test scores obtained by students are correct because of the influence of the learning model applied, not because of the experience of students or because they have studied system material nerves before. Guided Discovery Learning syntax consists of providing a stimulus, identifying problems, collecting data, processing data, and drawing conclusions integrated on Neurodroid media. The stimulus and problem finding stages can train critical thinking skills in interpretation. The teacher conducts question and answer sessions and guides students to formulate problems related to the problem. Furthermore, students are guided to formulate hypotheses relevant to problem identification. Each group conveys ideas to formulate hypotheses based on problem identification from the findings on the stimulus by following the teacher's guidelines in determining priorities in the investigation. Formulating a hypothesis can train critical thinking skills in aspects of analysis and concluding (Harahap, 2020). The process of student discussion in analyzing the reasons is carried out by each member before setting a hypothesis. After considering opinions and determining ideas from group members, students collected information from the Neurodroid media and presented material supported by pictures and videos to strengthen the hypothesis. Stage, to solve problems able to train students' critical thinking skills in analysis and explanation (Harahap, 2020).
Group members collect information and evidence from various literature to answer the problem. Furthermore, students can find and develop the concept of knowledge and end up at the analysis, discovery, and concluding stage. In line with Erikson & Erikson (2018), presentations are an effective and useful way to improve student's communication skills, increasing their critical thinking skills. The teacher and students discuss the results of each group in the form of validation or correction, confirmation and ending with withdrawal from the discussion process. Drawing conclusions can train students' critical thinking skills on withdrawal and self-regulation. Students who think critically will have confidence and offer responses to the conclusions made (Harahap, 2020).

CONCLUSION
The research and development that has been done show that guided discovery-based Neurodroid media significantly affects students' critical thinking skills. Students taught using guided discovery learning-based Neurodroid media increased 41.11 %. The developed media is expected to assist teachers in directing students to think critically because the media provides a stimulus at the beginning of learning in the form of pictures and then explains the material accompanied by pictures and videos in a complex and detailed manner. Likewise, the Neurodroid media is equipped with multiple choice practice questions to verify students' understanding. So that, when there is an incorrect answer, students want to review the material on the nervous system. The end of the media is closed in the form of conclusions from learning material on the nervous system. Integrated discovery learning with supported images and videos can hone students' critical thinking.