In the 21st century, people must have soft skills so that they can enter the workplace. One of the skills which must be acquired by students is critical thinking skills. Students’ low level of critical thinking skills is caused by the use of learning style that does not promote their thinking skills so that the students are not able to identify a problem, observe, and consider an observation result. Besides, the students are not able to make consideration, draw a conclusion, identify and consider a term. The purpose of this study is to analyse the effect of problem-based video animation instructions to improve students’ critical thinking skills. A quasi-experimental with one group pretest-posttest design was used in this study. The data were analysed using N-gain and analysed using the Wilcoxon test at a significant level of 0.05. The result of the study is p < α, which is 0.001 < 0.05. The conclusion of this study is about students’ critical thinking skills in terms of basic clarification, giving reasons for a decision, concluding and further clarification. This criterion indicates that the problem-based video animation instruction model is effective to improve students’ critical thinking skills.

The teaching and learning process in the classroom has not been able to arouse students 'learning motivation so that the learning motivation of students is not maximal, students' learning motivation is not maximized, seen from the learning process there are still students who have not been able to focus their attention and concentration on learning, so that only a few participants students who are active in learning. In addition, there are still many students who are not confident, do not dare to ask questions and when doing group presentations not all students dare to speak, only rely on other friends. The research approach used is quantitative with the type of quasi-experimental research, the research design used is Pretest-Posttest Non-Equivalent Control Group Design. The study population was all students of class 10th Senior High School 1 Peusangan and Senior High School 2 Peusangan, amounting to 252 people. The sampling technique used was purposive sampling, the sample in this study consisted of 140 students. Instruments to measure motivation using a questionnaire in the form of pretest and posttest questions. Data analysis consisted of normality test, homogeneity test, N-gain test, paired sample t-test and independent sample t-test, at a significant level of 0.05. The results showed that there were differences in the learning motivation of students in the experimental class and the control class on environmental pollution material in class 10th Negeri Bireuen district.

The critical thinking skills of class 10th from senior high school Banda Aceh students have not been trained in the learning process, students are not given the opportunity to analyze a problem, identify, conclude or come up with new ideas or an action on a problem. In fact, research shows that the learning process of biology in schools does not encourage students to think critically, thus affecting low learning outcomes. The research objective was to determine the increase in critical thinking skills in class 10th skills on the concept of environmental pollution and knowing the differences in critical thinking skills of class 10th students on the concept of environmental pollution in the experimental and control class. Data were collected from March to April 2019. The approach of this research is to use a quantitative, evaluation research type, the method used is quasi-experimental, with a factorial design group pre-test post-test. The sample in this study amounted to 253 students from two high schools in Banda Aceh. Essay questions are used to measure students' critical thinking skills. The data analysis used ANCOVA at a significant level of 0.05. Hypothesis test results show the value of ρ α, 0.00 0.05. The conclusion of this study is that the application of the PBL integrated with the mindmap can improve students' critical thinking skills. There are differences in students' critical thinking skills using integrated mindmapping PBL, PBL, mindmapping, and conventional.

The learning outcomes of students in class 11th Islamic Senior High School Banda Aceh are still low, the low learning outcomes of students in learning the motion system  concept in class 11th  Islamic Senior High School Banda Aceh are due to the teaching and learning process using practicum equipment on the concept of inadequate motion systems, this is evidenced by the laboratory space untapped and incomplete equipment. So that students are more likely to learn only from handbooks without direct learning experiences in real lifeThe research approach used is quantitative with the type of pre-experimental research, the research design used is the One-Group Pretest-Postest Design. The population of the study was all students of class  11th, amounting to 292 people. The sampling technique used was total sampling, the sample in this study consisted of 292 students. Pretest and Posttest questions in the form of reasoned choice test questions are used as instruments to measure learning outcomes. Data analysis consisted of normality test, paired sample t-test and N-gain test at a significant level of 0.05. The results of the paired sample t-test obtained ρ .001, so it was concluded that there were differences in student learning outcomes before and after learning with the application of the STEM-based Discovery Learning model on the motion system material in Islamic Senior High School 1 and Islamic Senior High School 2 Banda Aceh City. The results of the N-gain test using the Meltzer formula, the n-gain of learning outcomes obtained is 0.50, so the increase in student learning outcomes is in the moderate category.