The accuracy of assessing the capabilities of the process and product in chemical practice activities requires appropriate measurement procedures to be followed. It is crucial to identify the components that can introduce bias while measuring student abilities during the measurement process. This study aims to identify the components or criteria used by teachers to assess student performance in practicum activities and analyze the quality of the rubrics developed. The study was conducted with the participation of three raters, 27 high school students, and nine assessment criteria. A quantitative descriptive approach was employed using the many-facet Rasch model (MFRM) analysis for measurement. The results of the MFRM analysis show no significant measurement bias, with data measurement facets fitting the MFRM model. The reliability of all the facets meets the criteria, and the scale predictor functions appropriately. While all students can easily pass four out of nine items, five items can only be partially passed by students. The assessment criteria that require special attention include communication skills, tools and assembly, interpretation, cleanliness, and accuracy when performing practicums. These criteria provide feedback for teachers and students to ensure successful practicum activities. The Discussion section of this study delves into the findings and their implications.

The purpose of this research is to strengthen pedagogical content knowledge (PCK) in designing laboratory activities based on small-scale chemistry approaches. This research is action research involving 60 trainee teachers with stages that include (a) Reflect; (b) Plan; (c) Act; (d) Observe; (e) Reflect (2nd); (f) Plan (2nd). Qualitative data were collected through (a) Questionnaires reflecting on experiences in practicing chemistry learning and responses to the importance of learning, (b) a Portfolio of chemistry practicum design, (c) documentation of the process of carrying out design, implementation, and practicum evaluation activities, (d) field notes, (e) reflection sheet, and (f) Portfolio of follow-up plans. The data is displayed through the R computation system with data pre-processing stages in the teacher's reflection text which includes basic cleaning, case folding, normalization, stemming, and deleting meaningless words. Display data in the form of word clouds, frequency expression diagrams, and tabulations. Descriptive narratives are used to analyze the documentation obtained in the action process. The teacher group demonstrated performance in implementing small-scale practicum activities. Teachers are increasingly skilled in modifying conventional laboratory equipment, minimizing the amount of chemical use, minimizing waste disposal, and increasing efficiency in the duration of practicum implementation. The follow-up plan for this activity includes quality improvement in aspects of (a) skill in using laboratory equipment, (b) understanding of chemical concepts, (c) equipment availability, materials, and work procedures, and (d) implementation of chemistry practicum.

Students in mathematics classes do not understand the importance of sociomathematical norms in learning mathematics. This causes sociomathematical norms not to be teachers' focus when learning mathematics. Besides, there is no standardized instrument for assessing this norm, so developing this instrument is necessary to measure socio-mathematical norms in learning mathematics. This study aims to create and verify the psychometric validity of the sociomathematical norm scale. This research used a survey method with 505 senior high school students from Jakarta and West Java as respondents. The results showed that 25 items had convergent validity, with a loading factor value of > 0.700, meaning they could be declared valid. Concurrent validity indicates that each sociomathematical norms indicator is valid as a whole. Discriminant validity shows that the average variance extracted value on the diagonal is higher than the other values, so each item is declared valid. It was concluded that each item of the sociomathematical norms instrument has accuracy in its measurement function. The reliability test shows that each sociomathematical norms item is declared reliable. The reliability value of the sociomathematical norm item is .99, and the person's reliability is .86. Thus, the instruments developed can measure sociomathematical norms in learning mathematics.