Three Parts of 21 Century Skills: Creative, Critical, and Communication Mathematics through Academic-constructive Controversy

This study aims to analyze the characteristics of critical, creative and communication thinking after participating in learning academic-constructive controversy. Sequential explanatory design with sequential phase design analysis was used for the test results of two classes of junior high school students. The results showed that the experimental group was better than the control group for creative, critical, and communication mathematic. Completeness of the characteristics of the three abilities is in line with the ability of students, but they experience obstacles to communicating. Unfortunately, this study is only limited to quadrilateral topics. Academic-Constructive controversy learning can be used to develop three skills or even develop character qualities going forward.

represent in various types, and interpret mathematically [24]. Communication is characterized by the ability of students to articulate mathematical thoughts and ideas verbally and in writing, the ability to listen effectively to the reason of their friend and repeating their explanation [1].
Sternberg [25] suggested learning to develop analytical thinking through; 1) analysis of issues, 2) evaluation of issues, 3) explain how 4) compare and contrast, and 5) judge the value of characteristics something. Whereas learning to develop creative thinking through; 1) create a problem, 2) inventory of new ways of solving problems, 3) exploration of new ways, 4) imaginative (what if), 5) suppose (what would have?), and synthesize. This learning must be based on a particular set of principles including 1) agency, 2) reflection, 3) collaboration, 4) culture, 5) deep discipline, and 6) developmental corridors [26].
Critical thinking can be developed effectively by providing opportunities for dialogue, exposure of students to authentic problems/examples faced by students, and giving guidance [27]. Critical thinking can be developed by creating a constructive learning environment by providing a context in the classroom [28], and to teach thinking through mathematics rather than remembering formulas [29].
Potential learning strategies are needed to develop students 'creative thinking abilities, critical thinking skills and inferential thinking skills and students' problem-solving abilities [30]. Teachers must create creative contexts in classrooms, monitor developments, encourage sharing of creativity [31].
Mathematical communication can be effectively improved through ASSURE learning (analysis, conditions, selection, use, needs, and evaluation) [32]. in addition, Socio Scientific Issues (SSI) are effective for developing basic communication components [7].
The study above shows the importance of learning strategies that contain mathematical contexts, learning constructive thinking environments, argumentative dialogue, mentoring the learning process. These four things are in line with the elements of cooperative learning [3,33]. which is contained in 2 main categories of cooperative learning namely argumentative dialogue and constructive thinking environment [33]. Furthermore, by providing intellectual conflict [34], called learning CAC (Constructive Academic Controversy) [35]. Which is then called learning Academic-Constructive Controversy [36].
Various benefits of CAC / CC have been recommended by researchers. These include high-quality decision making and group function improvement [37], growing team loyalty and innovation [39], developing risk-taking to improve innovation and recovery risk management [39], developing reasoning strategies, more critical thinking, more creative solutions to complex problems, building curiosity, and being able to view issues from various perspectives [34].
However, studies on the application of CAC / CC to mathematics are rare, especially in developing critical thinking skills, creative thinking, and communication. This study was conducted to explore whether the three skills can develop after following Academic-Constructive Controversy learning?

Procedures
This study aims to analyze the characteristics of critical, creative and communication thinking skills through sequential explanatory design [40]. The first stage of giving treatment in the form of learning CAC for the experimental class (Class VII-D) and expository learning for the control class (Class VII-C). The second stage, data analysis through 2 phases. The first phase is quantitative, where data is collected through descriptive tests to measure differences in critical thinking skills, creative thinking and student communication between the experimental and control groups. The second phase is called the qualitative phase, to explain more about the characteristics of the three abilities for the experimental group. Qualitative data were taken from 2 high group students, 2 medium group students, and 2 low group students. This qualitative data was taken from the results of interviews to explain the results of their test answers [41].

Data Collection Technique
Quantitative data is collected through descriptive tests to measure critical, creative and communication thinking skills. Critical thinking tests include basic classification aspects, basic support, inference, further clarification, and strategy and tactics [42] on the topic of building a rectangular flat with 6 items. Creative thinking tests include aspects of fluency, flexibility, originality, and elaboration with 4 items [20,43]. Communication skills test refer to the NCTM with a number of 6 items in question [44]. Qualitative data were collected through student answer documents and interviews were used to collect characteristics of critical thinking, creative thinking, and student communication skills [40].

Data Analysis Technique
Data analysis refers to the design of the sequential phase [45]. Quantitative analysis was used to assess the significance of differences in statistical critical, creative and communication skills between the experimental group and the control group. Qualitative analysis is used to examine the differences in the characteristics of critical, creative and communication thinking skills based on student categories. The examine is done with the Mann-Whitney U test.

Results
The results of the study in this study are arranged in 3 main parts. First, characteristics of students' critical thinking, characteristics of students' creative thinking, and thirdly differences in abilities and characteristics of student communication. The third difference in ability was seen statistically among students who attended CAC learning with those who participated in expository learning. The characteristics of the three abilities are seen qualitatively from the achievement of the third aspects of the ability of the experimental group students based on the group of high, medium and low students.

Differences and Characteristics of Critical Thinking
Critical thinking in this study includes 5 aspects, namely: basic clarification, basic support, inference, further clarification, and strategies and techniques. This data is then analyzed quantitatively and qualitatively. Quantitative data showed in the following Table 2.  Table 2 shows that the average critical thinking ability of students who followed CAC learning is higher than the average student who followed expository learning. In more detail, the average of each aspect of critical thinking skills between the experimental group and the control group can be seen in Figure 1 below; Figure 1. The average score aspect of critical thinking Based on the data in Figure 1, students who learn through CAC have a higher average for each aspect of critical thinking compared to students who learn through expository. The inference aspect is the highest aspect achieved by the experimental group students, while the Universal Journal of Educational Research 7(11): 2314-2329, 2019 2317 basic support aspect becomes the lowest aspect. Furthermore, to find out more about these critical thinking, interviews were conducted with several students. The following are a few examples of the results of interviews conducted through representation from every aspect (A), queestion (P), and level of students' critical thinking (T-S-R).   Furthermore, a qualitative analysis was carried out on 2 low-category students, 2 moderate category students, and 2 high category students. Based on the reduction of answer documents explored through interviews, it can be categorized the thinking skills of the experimental group as in the following Table 4.
Description: (√) shows students have been able to go through the stages, Strip marks (-) shows students have not been able to go through this stage Three Parts of 21 Century Skills: Creative, Critical, and Communication Mathematics through Academic-constructive Controversy The data in Table 4 show that high category student can go through all stages of critical thinking. High category student have the characteristics to be able to provide basic clarification, provide basic support, make inferences, provide further clarification, and are able to use strategies and tactics in solving problems related to a quadrilateral. Moderate-category student have less systematic characteristics of critical thinking where there is a jump in critical thinking from one stage to another in critical thinking. While low group students only have one or two stages of the characteristics of critical thinking and also non-systematic stages.

Differences and Characteristics of Creative Thinking
The creative thinking ability of students studied includes aspects: fluency, flexibility, originality, and elaboration. In general, the average creative thinking ability of the experimental group students reached score 2,62, while control group students reached score 1,62. While the achievement of each aspect of creative thinking for both groups can be seen in the following Figure 2. Based on the data in figure 2, the ability of each aspect of critical thinking of the experimental group was higher than the control group. The students becomes fluency, flexible, spark the ideas to use strategies to solve quadrilateral problems. This ability indicates that CAC learning can develop creative strategies in solving problems [34]. The stages of CAC learning can encourage creativity [31]. CAC learning becomes a potential alternative for developing students' creative thinking skills [30]. Statistically, the difference test was carried out using the Mann-Whitney U test to see the significance of the differences. The data in Table 5 shows that there are significantly differences in creative thinking skills between the experimental group and the control group. The creative thinking ability of experimental students is more developed compared to the control group students. This shows that CAC learning is potential and effective for developing students' thinking skills with the existence of stages or learning scenarios that can encourage students to think creatively.
Qualitative analysis showed that there are differences in the characteristics of creative thinking for high group students, moderate groups, and low groups. This differences in characteristics showed by the aspect of creative thinking such as aspects of fluency, aspects of flexibility, aspects of originality, and aspects of elaboration.
High group-students have the characteristic to generate lots of ideas and answers to solve problems, and they are very fluent in delivering in their language. These characteristics are in line with fluency aspects. While the group students are giving answers at the minimum request alone with a fair fluency explanation. On the contrary, low group students still experience illiteracy in generating ideas and not fluent in conveying their answers.
The following are the results of interviews related to creative thinking presented in Table 6.  Mathematics through Academic-constructive Controversy

[so the size of the rectangle is 12 with the width 8. The rectangle is divided into 3. So, the size is 8 width 4 width. Right if it is multiplied 8 x 4 = 32 x 3 = 96 m 2 )
R-1 4 Sebenernya tuh liat dari S13 Bu jawabannya.
[Actually, see from S13 for the answer ma '
[First select the size of the garden 20 x 6 then look for using the formula 2x20 + 6 to 52 m. because the distance between the trees is 2 so 52 divided by 2 to 26  The ability of various ways and variations in solving the problems faced, consider it, by looking at it from a different perspective held by high group students. The moderate group still has errors in making consideration and using the less varied method. However, this ability does not appear for low group students. In detail, the characteristics of creative thinking from each group of students can be seen in Table 7. The ability to detect errors in the answer • Not yet fully disclosed his own thoughts in resolving the problem; • The writing of the answers is still not systemic and cannot be understood.
• Not yet been able to disclose his own thoughts to resolve problems; •

Differences and Characteristics of Communication Thinking
The average value of communication skills of the experimental group reached score 70.92, while the control group reached score 51.42. In addition, the achievement of each indicator of communication of the experimental group students was also better than that of the experimental group students. This result is shown in Figure 3. The highest score was achieved on the second indicator for the experimental group and the control group, with respectively 3.16 and 2.71. Students are able to state the situation and relations between the length of the land and the area of land into a table and or graph. This ability indicates that the rest can explain ideas, situations, and mathematical relations verbally or in writing, with real objects, images, graphics. While the lowest score was achieved on indicator 5, reading with an understanding of a written mathematical presentation. Control group students have difficulty understanding the length of the thread as a circumference of the kite. Figure 3 shows that the communication skills of the experimental group are better than the control group. This indicates that CAC learning has a positive potential in developing students' communication skills. The existence of a mathematical context, constructive-thinking learning environment, argumentative dialogue [34,33], during the learning process CAC triggers the development of students' communication skills. This is reinforced by hypothesis testing with a significance of 5% which indicates the difference in communication skills of the experimental group students with the control group as shown in the following Table 8. Some of the problems presented for group discussions such as identifying quadratic traits give rise to the possibility of differences of opinion, both between individuals in groups or between groups. This results in good intellectual conflict in deepening student understanding. The ability to explain the properties of the images presented, expressing them in writing is an important aspect of communication to developing better for students after attending CAC learning [46]. During learning, they are accustomed to using oral and written abilities to convey mathematical ideas and thoughts [1].  3 Dicari panjang tanah ke D E F, kalau dliat itu ditambah 2 dari panjang tanah sebelumnya. Lebar dari setiap tanah itu sama 6 m. Jadi tinggal panjangnya dikali lebarnya yang 6.
[I found for the length of the land to D E F, if you saw it plus 2 from the length of the previous land. The width of each land was the same 6 m. So the length was 6 times the width.] T-7 3 Pertama cari panjang tanah ke D E F, kalau diteliti tuh Bu kelipatan 2 jadi terus ditambah 2. Lebar dari setiap tanah itu sama 6 m. Luasnya tinggal dikaliin aja Bu panjang sama lebarnya [First, found for the length of the land to D E F, if we examine it, the multiples of 2 will be added to 2. The width of each land is the same as 6 m. The area of living is just being multiplied by the same length, ma'am]
[I found with guessing ma'am. The C is 14 before adding 2 so it must be 16 Qualitative data analysis revealed differences in the characteristics of communication skill of high, moderate, and low groups. Differences in these characteristics can be classified based on each indicator. Table 10 below shows the communication characteristics possessed by each group of students. The data in Table 10 show that high group students have fulfilled the ability to connect problems to real objects, images, and diagrams into mathematical ideas. They are also able to explain ideas, situations, and mathematical relations both in writing in the form of tables and graphs with little technical error. Indications in expressing events in everyday life into mathematical language or mathematical models are also in the form of notations, formulas or symbols. They are also fluent in writing the properties of all rectangular flat shapes in a complete, clear and understandable manner. They can identify information that needs to be understood, the main problem in the problem, how to find a solution to the problem in the problem. However, students cannot fully find the right answer. In addition, they have the ability to create conjectors, form arguments, formulate definitions and make generalizations even though they are still incomplete and there are still errors. This finding supports Johnson et al., [34], where constructive controversy forms active students in seeking new information to complement perspectives so that reconceptualization and conclusion formulation are better.
Medium group students have fulfilled the ability to connect problems to real objects, images, and diagrams into mathematical ideas. They are also able to explain ideas, situations, and mathematical relations both in writing in the form of tables and graphs, although they are not systematic. Indications in expressing events in everyday life into mathematical language or mathematical models are also in the form of notations, formulas or symbols, although they are not neat. They tend to be able to write the properties of all flat rectangular shapes completely, clearly, and comprehensively. They can identify information that needs to be understood, the main problem, how to find a solution to the problem, although it has not been systematic and fully found the right answer. In addition, they have the ability to create conjectors, form arguments, formulate definitions and make generalizations even though they are still incomplete and incorrect.
Low group students have fulfilled their efforts to connect problems to real objects, drawings, and diagrams into mathematical ideas even though they are not correct. They also tried to explain ideas, situations, and mathematical relations both in writing in the form of tables and graphics even though they were still wrong. They are still incomplete in expressing events in everyday life into mathematical language or mathematical models and are not so neat that they are difficult to understand. They have difficulty writing down the properties of all flat rectangular shapes in a complete, clear and understandable manner. They have difficulty in identifying information that needs to be understood, the main issue is the problem, and how to find a solution, although it is not systematic and the answer is incorrect. They lack the ability to conjecturing arguing, formulating, and generalizing even though they are still incomplete and incorrect.

Discussion
The findings described above show that learning Academic-Constructive Controversy (CAC) has the potential to develop the 3 abilities needed in 21st-century skills, namely the ability to think critically, think creatively and communicate with students.
Students who take CAC learning are accustomed to holding dialogues and presenting the results of problem-solving in constructive learning environments [28] that provide opportunities for thinking through mathematics [29] making it effective for developing critical thinking. Students of the experimental class are accustomed to using logical thoughts to make conclusions [3] and dare to make decisions [47] relating to quadrilateral problems. The basic clarification aspects of the experimental group students are also high. They can provide simple explanations relating to quadrilateral properties The stages of CAC learning are able to encourage creativity [31]. CAC learning can develop creative strategies in problem-solving [34]. CAC learning becomes a potential alternative for developing students' creative thinking skills The existence of a mathematical context, constructive-thinking learning environment, and argumentative dialogue [34,33]during the process AC learning triggers the development of students' communication skills. This is reinforced by several problems presented for group discussions such as identifying quadratic traits giving rise to the possibility of differences of opinion, both between individuals in groups or between groups. This results in good intellectual conflict in deepening student understanding. The ability to explain the properties of the images presented, expressing them in writing is an important aspect of communication [46], developing better for students after learning CAC. During learning, they are accustomed to using oral and written abilities to convey mathematical ideas and thoughts.

Conclusions
Based on the results of research and discussion can be concluded as follows: • CAC learning has good potential to develop students' critical, creative thinking and communication skills. Each CAC learning step that is carried out is able to develop one or both or the third of these abilities. CAC learning can be an effective alternative strategy for developing critical thinking skills, creative thinking, and student communication.

•
Aspects of critical, creative, and communication thinking skills are owned by high group students after participating in CAC learning activities. However, for the medium group and the low group, they have not fulfilled all aspects. Basic aspects of support in critical thinking, originality aspects of creative thinking, and aspects of reading with understanding a written mathematical presentation in communication still need to be developed.

•
The ability to communicate the idea of generalizing students still needs to be improved for students in the early grades in the level of education. This will be needed to be able to further increase their contribution in sharing ideas and ideas in mathematics in the following classes.
More in-depth studies are still needed such as examining the relationship of the stages of CAC learning with 4C, assessing CAC learning potential in developing life and career skills, such as adaptation, initiative, productivity, and social skills