Students’ critical thinking skills using HOTS-based assessment on pH calculation

One of the Indonesian government’s efforts to meet the 21st-century skills of students is to implement the curriculum of 2013. According to the Ministry of Education and Culture, the HOTS writing guidebook states that, in the context of 21^st-century learning, students must learn and master essential skills, including critical thinking, problem- solving, creative and innovative thinking, collaborating and communicating effectively, which are higher order thinking skills. Familiarising students to think critically makes students able to analyse a problem that occurs in society so that they can produce an idea or way to solve these problems. This research is qualitative research with the type of case study research and uses the analysis method of Miles and Huberman. The research subjects in this study were students last XI A and XI B MA Fathul Hidayah Pangean, with a total of 42 students. The results showed that the critical thinking skills of MA Fathul Hidayah Pangean students in classes XI A and XI B were 42 students classified as low, with an average percentage of 26,80%. Judging from the 5 aspects of critical thinking as a whole, it is relatively low. This is because students are not used to solving HOTS-based questions, so even though in mastering the pH calculation material, they can understand the material shown by excellent learning outcomes with a percentage of 82,7%, when faced with HOTS questions, student learning outcomes become 44,3% with medium criteria. This resulted in students’ critical thinking skills being still low.