This study is a series of Didactical Design Research in prospective analysis stage to comprehensively identify some obstacles in learning negative integer in order to capture how the learning process used by teachers and how the impact on students in understanding the concept of negative numbers. This research is a case study administered to seventh-grade students in one of the classes in a junior secondary school in Indonesia to investigate how the teacher managed the learning process of integers and identify students' thinking construction. Involving a mathematics teacher and 37 students, this qualitative study collected data from field observations, interviews and document review. The data were analyzed by the perspectives of learning obstacles based on Theory of Didactical Situation. Findings show how teacher describes the negative integers and the arithmetic concepts to the students and its contribution in causing misunderstanding on the students. Within the framework of epistemological obstacles, the result of this study is used as a basis for designing a learning program which can overcome problems related to teaching and learning of negative integers.

This study revealed how students' understanding of negative numbers and identified their difficulties related with the concept of integer and its counting operation as part of identifying epistemological obstacles about negative numbers. Even though teachers have explained counting operation procedure of integer, but there was concept misunderstanding among students. The concept difference between what was comprehended by respondents in their learning process and knowledge science has resulted in wrong perceptions about the negative numbers. In this article, the authors explained how these misunderstanding in concepts occurred among students and how these ideas were expressed by the students in solving the problem which was related with counting operation of negative integer. This study was part of Didactical Design Research using qualitative approach in negative number learning by involving 96 students of 7th grade as participants in three different schools. This study showed some difficulties by the student to understanding negative numbers in terms of prerequisite knowledge, understanding concepts, procedures, principles and problem solving.

Penelitian ini bertujuan untuk mendesain Hypothetical Learning Trajectory (HLT) pada pembelajaran bilangan negatif sebagai hasil dari tahap pertama Didactical Design Research yaitu Analisis Prospektif. HLT ini merupakan tindak lanjut dari hasil identifikasi Learning Obstacle yang yang dilakukan peneliti dalam pembelajaran bilangan negatif yang terintegrasi dalam materi Bilangan Bulat di kelas 7 sekolah menengah pertama. Observasi mendalam terhadap proses belajar mengajar di kelas yang diamati peneliti memperlihatkan kesulitan guru dalam menanamkan konsep bilangan negatif dan operasi bilangan yang melibatkan bilangan negatif serta beberapa kesalahan konstruksi konsep yang dialami oleh siswa. Istilah HLT merujuk pada rencana pembelajaran berdasarkan antisipasi belajar siswa yang mungkin dicapai dalam proses pembelajaran yang didasari pada tujuan pembelajaran matematika yang diharapkan pada siswa, pengetahuan, dan perkiraan tingkat pemahaman siswa, serta pilihan aktivitas matematika secara berurut. HLT ini disusun berdasarkan analisis terhadap Learning Obstacle, tahap berpikir siswa, dan analisis terhadap kurikulum dengan tetap berpijak pada konsep materi yang harus dipahami siswa.This research aims to design Hypothetical Learning Trajectory (HLT) on learning of negative numbers as a result of the first stage on Didactical Design Research specifically in Prospective Analysis. This HLT is a follow up of the results of the identification of the Learning Obstacle conducted by researcher in learning negative numbers that integrated in the material Integer in the 7th grade secondary school. From the observations conducted by researcher on the teaching and learning process in the classroom showed the difficulties of teachers in embedding the concept of negative numbers and arithmetic operations involving negative numbers and several construction errors of concepts that experienced by the students. Term of HLT refers to a lesson plan based on the anticipation of student learning possibly achievable in the learning process which is based on mathematics learning goals expected on students, knowledge, estimates of the level of students understanding, and the selection of mathematical activity sequentially. This HLT is compiled based on an analysis of the Learning Obstacle, level of students thinking, and analysis of the curriculum that standing on the concept that must be understood by the students.

High Order Thinking Skill or abbreviated with HOTS is an ability that is applied in the revised 2013 curriculum. The community service activities aim to (1) help teachers improve their understanding of learning outcomes evaluation, (2) improve teacher understanding of HOTS questions, and (3) improve teachers' ability to make HOTS questions, so that later HOTS questions are in accordance with the standards 2013 revision curriculum. This community service activity was carried out in the form of short training for three meetings. This activity was held in SMA Negeri 3 Tebing Tinggi, Empat Lawang Regency, South Sumatera Province, which was attended by high school teachers in Empat Lawang District. The method used in the implementation of this activity is the method of lecture, discussion, simulation and demonstration. The results of this activity were the increase in teachers' understanding of the HOTS problem and the teacher's ability to make HOTS questions. ABSTRAKKemampuan berpikir tinggi atau yang disingkat dengan HOTS merupakan kemampuan yang diterapkan dalam Kurikulum 2013 revisi. Kegiatan pengabdian masyarakat ini bertujuan untuk  (1) membantu guru dalam meningkatkan pemahaman tentang evaluasi hasil belajar, (2) meningkatkan pemahaman guru tentang soal HOTS, dan (3) meningkatkan kemampuan guru dalam membuat soal HOTS, sehingga nantinya diperoleh soal HOTS yang sesuai dengan standar Kurikulum 2013 revisi. Kegiatan pengabdian kepada masyarakat ini dilaksanakan dalam bentuk pelatihan singkat selama tiga kali pertemuan. Kegiatan ini dilaksanakan di SMA Negeri 3 Tebing Tinggi Kabupaten Empat Lawang Propinsi Sumatera Selatan yang diikuti oleh guru-guru SMA dalam Kabupaten Empat Lawang. Metode yang digunakan dalam pelaksanaan kegiatan ini adalah metode ceramah, diskusi, simulasi dan demonstrasi. Hasil dari kegiatan ini adalah meningkatnya pemahaman guru tentang soal HOTS dan kemampuan guru dalam membuat soal HOTS. Â

This study aims to produce an Animation Video-based Learning Media product on data presentation material that is valid, practical and has good effectiveness on student learning outcomes. This study uses the Research and Development model with 10 stages, namely potential and problems, data collection, product design, design validation, design revision, product testing, product revision, usage trial, product revision and mass production. The object of research is an animated video-based learning media in class VII data presentation material. The results of this study are in the form of animated video-based learning media which have advantages such as presenting the material displayed using animated media so that in addition to being easy to read, it is also more interesting to help the online and face-to-face learning process. Based on the analysis of animated video-based learning media on the data presentation material for class VII, the results obtained from aspects of validity, aspects of practicality and aspects of effectiveness. a) aspects of validity obtained very valid criteria based on the assessment of the validator with a total average score of 93%; b) practical aspects obtained practical criteria based on student response questionnaires with an average score of 86%; c) aspects of effectiveness on student learning outcomes with good criteria based on learning outcomes tests with a percentage of completeness of 81.8%.