Differential equations is a branch of mathematics which is closely related to mathematical modeling that arises in real-world problems. Problem solving ability is an essential component to solve contextual problem of differential equations properly. The purposes of this study are to describe contextual teaching and learning (CTL) model in differential equations course, to improve lecturers’ abilities in implementing CTL, and to improve students’ problem solving ability in differential equations. The study was conducted in the fifth semester of 2015/2016 academic year with 34 students of mathematics education Universitas Muhammadiyah Surakarta as participants. The CTL model was applied by lesson study approach which involved three stages namely plan, do, and see in each cycle. This research was conducted in four cycles. The study results found that discovery-based CTL could be applied in differential equations course. The lecturer abilities to design discovery-based contextual learning plan, to present real-world problem in learning process, to design learning strategy and assessment instruments of problem solving improved significantly. Problem solving ability of students also improved during teaching and learning process.

The study aims to 1) identify the teachers' problem to develop a development model of professional teachers with a lesson study-based approach at Muhammadiyah Schools of Sukoharjo regency, 2) find an effective lesson study model as a development model of professional teachers, and 3) analyze a lesson study validation as a development model of professional teachers. The research used a phenomenology descriptive-qualitative method. The subjects included the students, teachers, principals, department head of education, and members of the Regional House of Representatives. The techniques of the data gathering employed the observation, documentation, and in-depth interview. The technique of the data analysis applied the first order understanding and second order understanding. It could be concluded that the four problems to improve the teachers' professionalism with a lesson study-based model are as follows: 1) internal, 2) external (teachers' commitment and concern), 3) an effective lesson study model based on a plan-do-see circle, collaboration, and collegial tutor, and 4) a lesson study validation in relation with the validations of open lesson and reflection, theory, and implementation.

This study aims to describe: 1) the learning models used in the implementation of STEM education in Indonesia, 2) the level of education used in the implementation of STEM education in Indonesia, 3) the effect of STEM education in Indonesia on the students’ learning outcome. This is a literature review study, 27 articles were analyzed based on the research method, level of education, learning models, and learning outcome. A within-case analysis was carried out to analyze the articles in the dataset. The research result showed that: 1)STEM education in Indonesia was carried out by using the learning models: Project Based Learning (PjBL), 6E, HOTS assessment based-learning, inquiry,Think Pair Share (TPS), Problem Based Learning (PBL), android game, digital and student book based-learning, PjBL is the learning model which most widely used in the implementation of STEM education in Indonesia, 2) STEM education in Indonesia was conducted in elementary school, junior and senior high school, but very limited in university level, 3) STEM education in Indonesia was effective on the students’ learning outcome: scientific literacy, creative thinking, critical thinking, attitude, HOTS, character, achievement, problem solving, and 21st century skill.

Penelitian ini bertujuan untuk 1) mengembangkan lembar kerja peserta didik (LKPD) berbasis Higher Order Thinking Skills (HOTS) pada materi sistem persamaan linear dua variabel menggunakan konteks lingkungan, 2) menguji kevalidan dan kepraktisan dari LKPD berbasis HOTS yang dikembangkan. Penelitian ini merupakan penelitian research and development dengan model pengembangan Plomp yang terdiri dari tiga fase, yaitu investigasi awal, pengembangan atau prototipe, dan penilaian. Penelitian ini hanya dilakukan hingga fase pengembangan atau prototipe. Fase investigasi awal telah dilakukan sebelumnya sebagai dasar pengembangan lembar kerja peserta didik. Fase pengembangan atau prototipe terdiri dari kegiatan mendesain rancangan awal lembar kerja, kemudian melakukan penilaian lembar kerja melalui kegiatan self evaluation, expert review evaluation, one-to-one evaluation dan small group evaluation. Teknik pengumpulan data yang digunakan adalah wawancara dan angket. Proses analis data hasil wawancara dilakukan dengan analisis deskriptif, sedangkan hasil angket kevalidan dan kepraktisan dianalisis secara deskriptif kualitatif dan kuantitatif. Hasil dari uji kevalidan menunjukkan bahwa LKPD berbasis HOTS memenuhi kriteria kevalidan dengan skor 3,385. Hasil dari uji kepraktisan menunjukkan bahwa LKPD berbasis HOTS memenuhi kriteria kepraktisan dengan skor 3,288. Berdasarkan hasil kevalidan dan kepraktisan dapat disimpulkan bahwa LKPD berbasis HOTS pada materi SPLDV menggunakan konteks lingkungan layak digunakan dalam pembelajaran.