Abstract:
Learning activities that utilize a problem-solving approach are an effort to train students' critical thinking skills. However, to determine the success of learning that develops students' critical thinking skills, teachers should be able to measure the skills using the right instrument. This study is aimed to develop an assessment instrument to measure EFL learners’ critical thinking skills in writing expository problem-solution essays. The participants of the study were advanced students of Academic Writing who participated in the pilot study small and large scales. The analysis found that the scores yielded by the two raters were valid and reliable (r value obtained was .987 and α value for each component was higher than r table .320). Furthermore, the score on each component of assessment namely the depth of analysis was .640, the feasibility of solution was .667, the logic of argument was .795 and the use of evidence was .908. These scores are greater than the R table which means that the scores are valid. This suggests that the test instrument and the scoring rubric can be used in assessing EFL students’ critical thinking skills particularly on the ability to analyze an issue, propose suitable solution, provide logic argument, and use of relevant evidence.
