The ability to solve problems and logical thinking of students can be grown by studying Geometry. However, the reality in the field and some research in Indonesia shows that the geometric thinking ability of junior high school students is still relatively low. This study aims to examine the geometric thinking ability of junior high school students according to Van Hiele Theory. This research is a qualitative study with a descriptive approach, which was conducted in one of the junior high schools in Pringsewu Regency involving 28 students of class VIII. One student was selected to represent levels 1, 2, 3, and 4 Van Hiele as the research subject.  Data collection was carried out using multiple choice tests and interviews. Data analysis techniques were conducted with data reduction, data presentation, and conclusion drawing stages. The data originality technique was carried out by triangulation, in which the researcher compared the test data with the results of student interviews. The results showed that level 1 students (28.57%) could recognize and name geometric shapes visually; level 2 students (14.28%) could study geometric shapes by observing and mentioning the properties of the shapes; level 3 students (7.14%) could make connections between various geometric shapes and detect general properties of certain geometry; level 4 students (3.57%) could distinguish and make simple conclusions about the shapes and properties of shapes.
 Kata kunci: berpikir geometri, level van hiele, siswa SMP.

Pemahaman konsep merupakan hal yang perlu dimiliki siswa karena konsep-konsep dalam materi matematika saling berhubungan satu sama lain. Tujuan penelitian ini adalah untuk mengetahui desain pembelajaran materi rasio menggunakan konteks memasak nasi yang dapat membantu siswa Sekolah Dasar dalam memahami konsep rasio. Peneliti merancang lembar aktivitas siswa dengan konteks memasak nasi sebelum melakukan penelitian. Penelitian desain ini dilakukan pada siswa kelas VI salah satu SD Negeri di Belitang yang dilakukan dalam tiga tahap yaitu the preparing for the experiment, the design experiment, and retrospective analysis. Pengumpulan data melalui lembar aktivitas siswa dan wawancara. Teknik Miles dan Huberman digunakan untuk menganalisis data yang meliputi reduksi data, penyajian data, dan penarikan data. Hasil penelitian menunjukkan bahwa desain pembelajaran materi rasio menggunakan konteks menanak nasi dapat membantu siswa dalam memahami konsep rasio. Lintasan pembelajaran terdiri dari empat aktivitas, yaitu (1) menonton video memasak nasi, (2) mengetahui hubungan jumlah nasi dengan jumlah air pada proses memasak nasi, (3) membuat tabel rasio tentang jumlah beras dan jumlah air yang dibutuhkan dalam proses memasak nasi, (4) menyimpulkan pengertian rasio berdasarkan aktivitas memasak nasi.

This research aims to produce a learning trajectory that can help students understand the concept of circles using the Indonesian Realistic Mathematics Education (PMRI) approach. This research takes the context of the traditional game "gobak sodor" which developed from an informal form to a formal form. The research method used is a research design that involves three stages, namely preparing for the experiment, experimental design, and retrospective analysis. This research was carried out in eighth grade class in one of Junior High School in Palembang involving 34 students. PMRI is the basis for the learning context and activities in this research. Data collection includes taking student work results, interviews, and observations. The results of the research produced a learning trajectory that supports understanding the concept of circles from informal to formal form, which involves one activity of playing "gobak sodor," collecting data through observation and measurement, as well as interpreting data and observations. The results of the learning activities show that the series of activities carried out can help students understand the concept of circles.

Several earlier research investigated the use of Jigsaw to improve the quality of the online mathematics teaching-learning process. However, few studies have used the Jigsaw approach to improve the quality of online mathematics education, particularly in terms of motivation and learning results. To address this research gap, the goal is to outline the process of integrating the Jigsaw model in online learning and to demonstrate the importance of enhancing student motivation during the learning process. This study used the classroom action research approach, which involved 36 students from a high school in Central Java Province, Indonesia. The results of this investigation indicate that the application of Jigsaw can be done online using numerous procedures indicated in this study. Furthermore, the results indicate a considerable improvement in motivation and learning outcomes. The findings of this study are expected to serve as a reference for teachers on how to implement the Jigsaw model online.