The ability to think critically is a basic competency that must be possessed by students. This study aims to determine the level of critical thinking skills of junior high school students in Bima Regency, West Nusa Tenggara, Indonesia. Various studies have been carried out that explain how important students' critical thinking skills are, but there have not been too many studies on efforts to develop and empower students' critical thinking skills in a practical way. In this thesis, we introduce the technique of empowering students' critical thinking skills by developing a virtual laboratory media based on problem based learning on the material of the human excretory system. In this development, use software construct2 to develop a device which is then integrated with a problem based learning model. It is proven that a virtual laboratory based on problem based learning can improve the critical thinking skills of junior high school students in Belo Kaputen Bima District. We hope that the development of PBL-based virtual laboratory media can improve dramatically, such as the use of 3-dimensional and 4-dimensional software to improve students' understanding of critical and constructive thinking without losing quality.

This study aims 1) to determine the effectiveness of the Mind-Mapping based Aptitude Treatment Interaction model towards creative thinking and 2) to explain the mathematical creative thinking process based on the creative level. The number of participants was 26 students who took the Multivariable Calculus course in the odd semester of 2020/2021. This research used the mixed-concurrent embedded method. The data collection techniques were validation, observation, creative thinking tests, and interviews. The results showed that 1) the Mind-Mapping based Aptitude Treatment Interaction model was effective in developing creative thinking, as indicated by the average creative thinking score of the experimental class, which was higher than the control class and 2) the characteristics of students mathematical creative thinking process varied following the creative thinking levels. The students mathematical creative thinking level consists of not creative (CTL 0), less creative (CTL 1), quite creative (CTL 2), creative (CTL 3), and very creative (CTL 4). Students at the CTL 2, CTL 3, and CTL 4 can meet the aspects of fluency, flexibility, and originality.

The ability of students to build problem-solving models using procedural knowledge can be viewed from several aspects, including Mastery of Mathematical Problem Solving (MPS), understanding concepts and application of concepts, the relationship between learning outcomes of mathematics and interest in learning, and examine the contribution of the ability to understand concept problems, the application of concepts to the ability of MPS, as well as student difficulties and some of the advantages of students in solving problems. This experimental study aims to explain the effect of the MPS model using procedural knowledge on solving mathematical problems for Junior High School Students (JHSS). The findings showed that 1) The MPS method using procedural knowledge significantly improved learning outcomes, but the mastery of MPS for JHSS was still unsatisfactory. 2) MPS teaching could still not improve meaningful learning outcomes. However, when JHSS applied the concepts, calculations, and problem-solving aspects, MPS teaching improved meaningful learning outcomes. 3) Students' interest in learning mathematics in the two sample classes was classified as positive. Shortly, MPS teaching accustoms students to think systematically and creatively and not just give up on the problems they face.

In terms of learning and academic level, this study compares the development of mathematical creative thinking skills between students who use the Blended Learning Model with GeoGebra support (BLM-G) and students who use the Blended Learning Model without GeoGebra aid (BLM-non-G). A nonequivalent control-group design and a quasi-experimental research methodology are being used. The participants in this study were eighth-grade SMPN students in Ternate City, Indonesia. The research sample was 125 people from two schools with different grade levels. The instrument used is a mathematical creative thinking ability test. Research result; Learning using BLM-G influences students' mathematical creative thinking abilities at high and medium school levels, with very high categories. When compared to kids who learn using BLM-non-G learning, students who use BLM-G learning exhibit greater growth in their capacity for both mathematical and creative thought. This is based on high school level pupils. Kids who study using BLM-G learning and students who learn using BLM-non-G learning exhibit equal increases in their capacity for mathematical and creative thought at the middle school level.

This study aims to describe the implication of the Aptitude Treatment Interaction (ATI) model integrated with character values to increase the students’ skill in solving mathematics story problems. This study applied a quasi-experimental research type using a non-equivalent control group design involving two classes with 30 students each. Data was collected using a test instrument for solving mathematics story problem. Data were analyzed using n-gain descriptive statistical analysis to see the increase in students' skill in solving mathematics story world problems. The results showed that the average score of student's aptitude in solving mathematics story problems is 91.26 which is in the category of very high. There is an increase in the students’ ability with score of an n-gain of 0.77 which is in the category of high. In addition, the results of observations related to the implementation of learning model of the ATI with a percentage of 87.5% in the category of very good. Thus, the character-based ATI learning model can be used to increase the students’ skill in solving mathematics story problem. In addition, it accommodates the character of students who are concerned with learning mathematics so that learning goals can be achieved both from cognitive and attitudinal aspects.

Recent studies in mathematics education have focused on students' geometric problem-solving abilities, self-regulation, and the problem-based learning (PBL) model. The goal of this study is to examine how well junior high school students' self-regulation and geometric problem-solving skills are enhanced by the PBL model. In this study, quantitative methods using a quasi-experimental design were used. The sample consisted of 45 students from Amanatul Ummah junior high school in Mojokerto, Indonesia. Five types of instruments were utilized to collect data for this research, namely Syllabus, lesson plans, student worksheets, Self-Regulation Questionnaire (SRQ), and Geometry Problem-solving Test (GPST). The outcomes of the N-Gain test demonstrated how well the PBL model works to help students develop their capacity for self-regulation and geometric problem-solving. Apart from that, there are some notable differences between the traditional technique and the experimental class that is taught using the PBL paradigm. It is advised that similar trials be conducted in the future with a larger population and sample size. In both public and private junior high schools, it is strongly advised that more research be done with a larger population and sample size. Future researchers can also expand the study materials of geometry, not only to flat-sided geometric shapes but even further to curved-sided geometric shapes and also other subject matters.

Scaffolding dialogue is a concept in learning that refers to the support or assistance given to individuals during the dialogue process. The main objective of this research is to create a basic structure of dialogue to help and support students during the learning process in improving their algebraic reasoning skills. Algebraic reasoning is a process in which students generalize mathematical ideas from a certain set of examples, establish these generalizations through argumentative discourse, and express them in a formal and age-appropriate way. The study was designed using the grounded theory qualitative model method, which used three sequential steps: open coding, selective coding, and theoretical coding. The research was conducted on students of the mathematics education department at Universitas Islam Sultan Agung. Data collection methods include algebraic reasoning ability tests, questionnaires, and interviews. Data analysis in grounded theory is an iterative and non-linear process that requires researchers to constantly move back and forth between data collection and analysis. This process aims to produce a theory that is valid and can explain phenomena well based on empirical data obtained during research. The dialogue scaffolding strategy framework in improving students' algebraic reasoning abilities includes instructing, locating, identifying, modeling, advocating, exploring, reformulating, challenging, and evaluating.