Learning media was used to explain the theory and minimize misconceptions. 50% of physics teachers in East Java have difficulty creating learning media of circular motion. Therefore, researchers created an innovation learning media and analyze the perception of physics teachers to Arduino-based "Rotating Wheel" learning media (ABRW). This research used R&D design with a 4-D model. The subjects were 24 physics teachers throughout East Java and 35 students's XII MA Jabal Noer, Sidoarjo. The instruments used the form of teacher and student response questionnaires and material expert validation sheets. The data analysis is the calculation of the average value of validation results. The result from the physics teacher's and student response more than 65.8% and 75% in very positive category and validation more than 85% with a very valid categori. Thus, it was concluded ABRW props are feasible to use as well as learning physics in a circular motion topic.

The purpose of this study was to analyze the scope related to the subject of problem-solving skills based on multiple representation in 2016 – 2020 with 20 documents through bibliometric analysis. The research method used was a literature study through all the articles analyzed in this study. The articles were taken from the Scopus database with sampling in 2003 – 2020, resulting in 29 scientific work data exported in *.ris (RIS) and *CVS formats. Then, those data were processed using VOSviewer and Microsoft Excel. The results of publications in the last five years have increased. Indonesia is the dominant country in publicizing papers about this topic. Institutions from Germany managed to publish most of the documents about multi representation. Meanwhile, Poland is the origin country of the authors with most publications. The visualization of research trends on multi representation resulted in four main clusters: (1) multi representation related to students, representation, and learning processes (2) multi representation as a class (3) multi representation related to the problem (4) multi representation as a model and process. Meanwhile, Indonesian researchers are very active in contributing to this topic, in line with the number of publications by country, namely Indonesia.

This study aims to analyze research trends related to PjBL-STEM topics in 2016-2020 through bibliometric analysis with the Scopus database. Based on the criteria, it obtained 1,169 documents. Microsoft Excel was used to analyze data and VOS viewer as a data visualization. The results showed that PjBL-STEM research is increasing every year. The USA contributes the most research in the world, Indonesia ranks second. Universitas Pendidikan Indonesia, Universitas Negeri Malang, Universitas Sebelas Maret, and Universitas Negeri Semarang are among the top affiliates in PjBL-STEM research in the world. Visualizing the trend of PjBL-STEM research in 2016-2020, there are three clusters, namely 1.) PjBL-STEM as a framework, 2.) PjBL-STEM as self-development, and 3.) Effects of PjBL-STEM research. The results of this study can help researchers related to PjBL-STEM research trends in the world and provide direction in further research.

This research aims to analyze the implementation of multi-representation learning on climate change topics integrated fluid dynamics to improve students' problem-solving skills and analyze student responses to multi-representation learning on climate change topics integrated fluid dynamics. The type of this research is quantitative research with a pre-experimental that uses a one-group pretest-posttest design. This research was conducted in XI MIPA-1 at Senior High School 4 Sidoarjo with 36 students. Data collection techniques in this research used tests with test instruments in the form of description questions and questionnaires (responses) on a Likert scale. The data analysis technique is N-gain for the description test instrument and descriptive for student response questionnaires. The results of this research obtained the score of N-gain is 0.565 with a category of the medium. The results of student responses carried out using a Likert scale questionnaire for ten statements had positive and very positive results with a percentage of more than 77%. Thus, it was concluded that learning multi-representation could improve students' problem-solving skills with the topic of climate change integrated with fluid dynamics and elicit positive and very positive responses from students.