The development of problem based learning-based virtual laboratory media to improve critical thinking ability of junior high school students

This study aims to determine the effectiveness of the development of a virtual laboratory on excretory system materials. By using 60 students at SMP N 2 BELO. Data analysis from experts or experts consists of 3 media experts, 3 material experts, and 3 linguists. The validation results from the experts are distributed through a questionnaire/questionnaire then its validity is tested using the Aiken’s Coefficient Value test. The percentage of the feasibility of the virtual laboratory based on the results of the assessment of media experts is 92%, material experts are 92% and language experts are 91%. Meanwhile, the percentage of media eligibility based on a limited-scale trial conducted on 60 students was 80.54% with a worthy category for a large-scale trial. The advantages of the developed virtual laboratory products include: (1) the product is equipped with a pretest and posttest. (2) the product is synchronized with the Student Activity Sheet to reduce misconceptions. (3) the product is programmed offline. (4) the product is programmed to be accessible on android/smartphone. Suggestions for further study of the virtual laboratory should be researched based on combined quantitative-qualitative methods to determine the level of effectiveness and describe the findings.