Critical thinking as one of the 21st century competences required by students needs to be developed and analyzed by employing qualified assessment instrument. Test is a kind of critical thinking assessment instrument which quality is developed and analysed to create a meaningful learning. A total of 10 multiple choices items were developed based on critical thinking indicators. The items were then given to forty two 4th grade students in one of the elementary schools in Tasikmalaya-West Java after obtaining STEM learning. Focus group discussions were conducted to construct and validate the instrument. The result of the test was analyzed using Rasch model with the assistance of Winsteps software version 3.75. The results indicated that the analysis using the Rasch model could explain the critical thinking items’ quality based on the level of difficulty and suitability and could categorize students’ abilities and their suitability for STEM learning conducted.

The concept of air-having pressure needs to be understood by students so that they can understand natural phenomena related to the air concept. The characteristic of the abstract concept of air having pressure leads students to misconceptions. The purpose of this study is to analyze changes in students' conceptions of the air-having pressure concept by using the POE strategy. The research method used was a pre-experiment with one group pretest-posttest design. Pretest and posttest questions were given to students using the five-level diagnostic test instrument with a total of three questions. The ability to predict-test and the ability to observe-test were performed with four questions on each test. The participants of this study consisted of 31 fifth grade students in the even semester. The categorization of conception change is divided into five patterns: construction, revision, static, disorientation, and complementation. Based on the analysis, revision had the highest percentage followed by construction. The conclusion is that the POE strategy can help students in understanding the concept of air-having pressure so that there was a change from misconception to understanding scientific concepts.

Learning science in elementary schools encourages students to understand the natural environment more deeply, rationally, and scientifically. However, often the scientific concepts they believe about science topics are not in accordance with the scientific concepts they should be. This misconception is difficult for teachers to diagnose. Special instruments to identify and analyze students' misconceptions are needed. Therefore, this research aims to analyze the misconceptions of elementary school students on the topic of energy using a four-tier diagnostic instrument. The purposed-designed survey method was used in this study. The data were analyzed quantitatively and qualitatively. The participants in this study were 20 fourth grade students in an elementary school in Ciamis Regency. A total of 6 questions in the form of a four-tier diagnostic instrument were used to determine the level of students' conceptions. The results showed that the students have misconceptions about the concept of energy. This can be seen from the average percentage of students' misconceptions of 66.67%. This research is expected to contribute to alternative ways to identify and analyze students' misconceptions using the four-tier diagnostic instrument. In addition, it can be used as a reference for teachers and researchers related to the problem of misconceptions of science in elementary school students

The existence of media in geometry learning can assist the students to understand the concept. One of the media used in geometry learning is a pop-up book. This study aims to describe the perception of elementary school teachers on the pop-up book media in elementary geometry learning. The qualitative descriptive research method was used in this study. The research instrument used is a questionnaire consisting of 11 questions in the form of multiple-choice and open-ended questions. Open-ended questions aim to reveal the teacher's views on geometry learning media in elementary schools, especially pop-up book media. 108 elementary school teachers from West Java and Central Java who teach in various classes participated as respondents. The results showed that: (1) Most of the teachers thought that the geometric concepts that were difficult for students to learn were the concept of combined volume with a proportion of 77.8%; (2) teachers who already know the term pop-up book are 67.6%; (3) teachers who agree that pop-up books are suitable for use as learning media for geometry concepts in elementary schools reach 96.3%; and (4) teachers who use pop-up book media in geometry learning only reach 13%.