The Development of Probability Material using Edmodo

This research is aimed to describe the process and to get product development of learning material using Edmodo. Learning material is developed in the form of interactive learning material using Edmodo. This research belongs to Research and Development (R&D). The procedure includes the steps of Borg and Gall such as conducting research, collecting information, planning and developing preliminary form product, preliminary field testing and main product revision, main field testing and operational product revision, operational field testing and final product revision, dissemination and implementation. Expert judgment conducts data validity with the average score of media expert 3.57 and 3.67 from the material expert with a maximum score of 4 on a Likert scale. Practicability is obtained by the implementation of learning materials in each meeting which has exceeded 75%. The effectiveness of the response questionnaire of the student has achieved 80%. The students have received instructional materials well. The result of focus group discussion (FGD) can be concluded that learning material can be used in the teaching-learning process in curriculum 2013.

culture and education stated that main resource of information is a way to reach all sides in giving information in education and teaching-learning process. One of the implementations that havebeen conducted is national examination with Computer Based Test (CBT). Furthermore, he conveyed that the use of technology is not only used for theexamination but also in teaching-learning process.
In thedigital era, most of thestudents have used various social media. Most of them prefer to use technology from smartphone, tablet, gadget and computer then anopen book or repeat material in school. It is also probable that bad information can turn up as well. Therefore, teachers must also use technology in theteaching-learning process.
Fast development of information technology can be used in theteaching-learning process as aprovider of online media. Online media is usually named as e-learning, a kind of teaching-learning process that uses electronic technology and the internet. Teaching-learning process with the internet can use Edmodo. According to Pitoy [10], Edmodo is a platform of social media for teachers and students to share idea, file, agenda, activity and task. Edmodo is aimed to help teachers in using social media in theteaching-learning process. Edmodo is almost same as Facebook. However, it is not as free as Facebook. Edmodo feature is a special design in education to make an interaction among teachers, students and parents.
The government expects that developed technology can be used well in education. Utomo has developed e-learning material basis Edmodo in lithospherematerial of geography subject. Based on the above explanation, theresearcher will develop interactive material through social media of Edmodo [14]. Development of Edmodo material is expected to create high thought skill of probability. It can also facilitate students to use acellphone or tablet and internet service as learning media. Tomlinson added material development is what the writers, teachers, and students conduct to give input resource as a designed experience to improve learning [13]. Therefore, amaterial using Edmodo is expected to give easy way when the students want to repeat material and facilitate them to be independent in learning.

Method
This research uses research and development method. This research modifies the Borg & Gall model of research and development [1]. Education research and development is a process that is used to improve and validate an education product such as teaching-learning model, instrument, textbook, module, and media [1]. The following are research procedure of this research: 1) Collecting research and information: in this stage, researcher conducts a literature review about level probabilistic thought, analyses students' level probabilistic thought, observation and interview with the teachers. 2) Planning; it is conducted by defining, arranging interactive material design with aworksheet, determining material arrangement. 3) Developing preliminary form product; it includes preparing material or content design and producing amaterial draft in which product form that is developed is an interactive material with theworksheet. Afterwards, it is well kept by using Edmodo.4) Testing preliminary field and revising main product; it is conducted to state that the previous product has been valid with average valid criteria more than 2.5 with thescale of Likert (1-4). 5) Testing themain field and revising operational product; researcher conducts limited experiment towards developed material. The limited experiment is conducted by teaching ten students using Edmodo material. After conducting alimited experiment, revision is conducted based on the result of thelimited experiment through response questionnaire that has been validated by the experts. 6) Testing operational field and revising final product; it is conducted by applying theproduct in theteaching-learning process. Validated lesson plan must be preparedfor this testing. The operational testing field is conducted in a class that is chosen randomly to get practical and effective data.
The used instrument is material observation sheet for practice and response questionnaire for effectiveness. Criteria for practice is obtained if the percentage is more than 75% [8]. It is scored by two observers with statistical analysis "percentage of agreement" Grinnel [8]. An effective data product is obtained from theresult of response questionnaire using Edmodo in Poll feature. Effective criteria product is observed by students' response towards product implementation if no more than 80% of students give positive average result toward the developed product [12]. Furthermore, to declare valid product whether it is practical or effective, Focus Group Discussion (FGD) is conducted through assessment of practitioner or teachers.

Results and Discussion
Development process starts from research with data that is obtained probabilistic thought level. Collecting information is obtained from observation and teachers' interview. Data of probabilistic thinking level is mostly in subjective and transitional level. Observation shows that teachers use material from official government. The same result is also obtained from teachers' interview in which the material is from compulsory book and worksheet. Therefore, it is needed to develop interactive material with thetechnological element.The idea will be supported because school has adequate facility and students has smartphone that can be used to study Steps of product arrangement are planning and developing preliminary form product by designing material content and teaching-learning and producing material. The resulting product is interactive material. The form is interactive multimedia that can be accessed by smartphone or computer. The material will be completed with theworksheet. According to Depdiknas [2], theInteractive material is arranged based on theprincipal of material development, such as 1) starting from easy to difficult, and from concrete to abstract. 2) repetition will strengthen understanding, 3) positive feedback will give strength towards students understanding, 4) high learning motivation is a factor of successful learning, 5) achieving success seems like rising stairs, step by step and finally it will reach the top, 6) knowing result that will be achieved encourages students to continuously achieve the aim. Probability in theinteractive material is arranged based on main competence of Junior high school in curriculum 2013. Display of interactive material is shown in Figure 1. Next step is preliminary field testing and main product revision. Experts conduct preliminary field testing by scoring related product that is developed from media and material aspect. The experts are lecturers of mathematics education of Sebelas Maret University (UNS), informatics technique of UNS, thetechnique of information and computer education of UNS and outstanding teachers. The experts have previously ever made teaching material and media. Data for avalid product with anaverage percentage of three validators is shown in Table 1. 3.59 very valid Main product revision is conducted by improving thecontent and material display (interactive material and worksheet) as the experts suggest. After conducting revision, there will result in interactive material as below:

Figure 2. Display of Interactive Probability Material
The interactive material contains probability material that has been arranged orderly. It starts withrecognising experiment and statistic experiment, differentiating experiment and statistic experiment, sample point and sample space, recognising possible, impossible, and certain event, empirical and theoretical probability of an experiment, differentiating empirical and theoretical probability and probability complement of an event. The valid interactive material is completed with theworksheet. The interactive material can be accessed through asmartphone. However, the display adjusts with the smartphone screen of each user.
Next step is main field testing and operational product revision. It needs to prepare response questionnaire to know thereadable product that is developed. Main field testing is conducted by using interactive material and worksheet. It is taught to 10 students who are chosen randomly. Before testing, students have had Edmodo account because it has been able to be downloaded. The limited test result is obtained from thevote of students through Edmodo or response questionnaire. The result of response questionnaire obtains apercentage of 89.10 %. It means that students can accept material well and use it as alearning source. Operational product revision is conducted based on aquestionnaire, students' suggestion and researcher's note as material for revision.
The sixth step is operational field testing and final product revision. An instrument that must be prepared is arranging lesson plan that adopts the use of developed material and observation sheet of conducting material. All teaching-learning process that includes introduction, content, and closing is conducted by using interactive material and worksheet. The teaching-learning process is conducted in agroup. Each group use one laptop, and each student is given a worksheet. Before conducting teaching-learning process, lesson plan and observation sheet are validated by three experts. The result of teaching-learning includes planning of lesson plan, observation sheet and response questionnaire that stated lesson plan couldbe conducted, observation sheet can be used to measure the material conducted, and response questionnaire can be used to measure the acceptance of students' material.
Operational field testing is conducted in a class to know practicability and effectiveness. Practicability is based on observation result with material observation sheet in theteaching-learning process. Observation result of 2 observers in the first meeting is 93.75% and in the second meeting is 100%. According to Borich [8], criteria of practicability is more than 75%. Effectiveness based on response questionnaire is 93.25%. It means that students can accept material well. Besides that, notes from observers and students can be used as aremedial and teaching-learning process.
Final product revision is the last step that is conducted in this development process. This last step is aimed to reveal aproduct that is developed. It is a valid, practical and effective final product. It is discussedin Focus Group Discussion (FGD) with mathematic teachers. The process of FGD uses assessment sheet filled by five teachers. The average of assessment result and comment is 3.82. It means that the developed product is very valid. Comments can also be used as amaterial alternative which can be used in theteaching-learning process. The interactive material can help students to understand theconcept of probability because theabstract material can be represented in animation as mentioned in research result of Yung and Pass [17] related to the influence of visual representation and computer on mathematic learning. The result of teaching-learning mathematic with visual representation by using acomputer can support teaching-learning process, transform abstract mathematic concept and give influence on cognitive skill. The following is the display of interactive material and worksheet as the last product of development process.

Figure 3. Final Product of Probability Material
The use of Edmodo has not been effective yet since many students have not been accustomed to asmartphone to study. According to Hankins, teaching-learning result using Edmodo does not give significant influence towards students' achievements [16]. However, Edmodo helps students to study. Besides that, students are taught to use technology. Research of Wardono also supports this case; he found that e-learning using Edmodo gives good result in developing theliterate skill of junior high school students [15]. Furthermore, research conducted by Jun shows that only 4 % of students do not understand probability concept [6]. It can be concluded that the step conducted can improve concept understanding of probability.
The development process of material using Edmodo is an introduction. It includes research and collecting information. Development step includes planning and developing an early product, testing field and revising, testing the main field and revising, testing operational field and revising. The result of introduction step shows that probabilistic level of students is on the subjective and transitional level. Collecting information is obtained through interview and observation. In the step of product development results validity with average 3.57 from media experts and 3.6 from material experts. Validator experts state that Edmodo can be used in the teaching-learning process. It is also suitable with the basic competence of probability. Practicability means that percentage of material using Edmodo has achieved an average of more than 75%. Effectiveness also shows that students well accept Edmodo with response percentage of 93.25%. The result of FGD shows that material using Edmodo can be used and expanded in the teaching-learning process.
Learning material of probability using Edmodo can be used to the learning process of mathematic either inside the class or outside the class. Learning material of probability can help students to understand the concept of probability and to increase the level of students' probabilistic thinking.

Conclusions
Conclusions of this study are: (1) the ability to think critically mathematical junior high school students are still, (2) in terms of cognitive styles critical thinking skills mathematical junior high school students with a higher FI cognitive styles of the students FD, (3) From the aspect of students' critical thinking aspect with FI cognitive style is better than the FD on the viability inference, assumptions, deduction, and argument evaluation.