Nowadays, mechanical experiments such as spring oscillations for high schools and colleges have been developed using smartphones. This study aims to compare the use of acceleration sensors and video tracker available on smartphones for free and damped spring oscillation experiments. This experiment used varying load masses. In experiments using acceleration sensors, acceleration versus time data were obtained, while experiments using a video tracker got position versus time data. The data were then calculated to obtain the spring constant value and the damping coefficient are obtained. The experimental results showed that for experiments using the acceleration sensor, the spring constant values k = (11.8 ± 0.2) N m−1. For experiments using a video tracker the spring constant values k = (12.1 ± 0.4) N m−1. Experiments using the acceleration sensor can explain the acceleration trends that change periodically whereas when we use a video tracker it explains the trends in positions that change periodically. But, based on the standard deviation, showing that experiments using acceleration sensors obtain more precise results. We hope that mechanical experiment using smartphone acceleration sensors can be applied in physics laboratories on high schools and colleges, because that is easy, inexpensive, and also the results are more precise.

Newton’s second law can be demonstrated by classical mechanical experiments, one of which is using the Atwood machine. Atwood machines consist of two weights suspended by a rope and connected by a pulley. In this study, an Atwood machine experiment was carried out, where the smartphone was placed on one of the loads, so that the vertical acceleration of the motion system could be measured easily using an acceleration sensor. We also consider the effect of pulley rotation which is usually missed from previous studies. By deriving the second law equation of Newton on rotational and translational motion, we can get the relationship between the system acceleration and the gravitational acceleration of the earth. The results of the earth’s gravitational acceleration obtained, compared with the results of the experiment using a stopwatch (conventional method), and with the value of the standard earth gravitational acceleration at that place. Earth’s gravitational acceleration from the experiment using a smartphone is closer to the standard earth gravitational acceleration value than using a stopwatch. So, in this experiment, the use of a smartphone acceleration sensor contributes to enhance a conventional demonstration of classical mechanics experiments.

The purpose of this study is to analyze the effect of "Environmental Pollution Game-Based Learning (EPGBL)" on improving students’ conceptual understanding and environmental awareness. EPGBL is an android-based learning media that can be used in science learning, particularly for environmental pollution concepts. Quasi-experimental research with pretest and posttest group design was utilized to answer the research questions in this study. The average percentage of correct responses in the pre-test is 61.33, meanwhile, the percentage of correct responses in the post-test is 73.33. This result showed that the percentage of correct responses in the post-test is higher than in the pre-test. The results showed that EPGBL can improve students' conceptual understanding of environmental pollution concept. The average score of the students' environmental awareness character is 3.98 that include in the good criteria. In conclusion, EPGBL is effective in improving students' conceptual understanding and environmental awareness.

The period of the COVID-19 pandemic has forced all activities in educational institutions to maintain distance and all material delivery through unusual media and methods. To get around this unfavourable situation, online methods are one of the most effective options to overcome it. This research aims to analyse the most expected virtual class model on science learning based on student’s perspective. This research is a case study conducted through a survey method using an online questionnaire using google form. The subjects of this research were all students of basic science courses in the Science Education Study Program Faculty of Mathematics and Natural Sciences Universitas Negeri Semarang on odd semester of 2020. The results of this research indicate that the types of virtual classes implemented in basic science courses consist of LMS, LCMS, SLNs, combination of LMS-SLNs and LCMS-SLNs. The virtual classroom model implemented in science learning is in accordance with the objectives that include connectivity, flexibility, interaction, collaboration, development opportunities and motivation. The most expected virtual classroom model in science learning during the Covid-19 pandemic based on student perspectives is a combination of LMS-SLNs of 66.23%, LMS of 23.38%, LCMS-SLNs of 6.49%, and LCMS of 3.90%. The conclusion of this research indicates that the combination Virtual Class model of LMS (Learning Management System) and SLNs (Social Learning Networks) is the most expected according to student perspectives.

In the current pandemic era, learning process must be counduct online, including for assessment. To support online assessments, it is necessary to use information technology. A good and valid application for online assessment offered in this study is Quizizz. The purpose of this study is todetermine student responseapplication of online exams using the quizizz.The research subjects were students of science education, Universitas Negeri Semarang. The exam is a midterm of astronomy course. The method of research carried out includesthe applied method, responding to quizizz in conductinglearning assessments of multimedia learning. Theresults showed that students were very responsive tothe application of the quiz during the midterms, thoughthe mean score was still low (43.08% with a standard deviation of 15.83%), but students accepted the resultsand try to fix it. For the questionnaire, student responses to the use of Quizizz tend to be positive with the results of 8 statements getting positive responses of more than 50% of the total students.The Quizizz presents the problem with easeby analyzing the results of the detailed answers to help teachersor lecturers in carrying out the assessment.