The purpose of this study was to develop a reliable and valid rating scale for the use of the assessment and evaluation of lesson plans and teaching practices that are based on argumentation-based inquiry (ABI). The study covered two academic years (four academic semesters). Qualitative and quantitative methods were utilized throughout the development of the rating scale including data collection and data analyses. A purposive sample of 72 pre-service science teachers (PSTs) who were enrolled in a public university located in East Black Sea region of Turkey constituted the sample of the study. Content Validity Ratio (CVR=0.80) and Content Validity Index (CVI=0.94) values were calculated as measures of content validity. Pearson Correlation Coefficient (r=0.96) and Cohen's Kappa value ([kappa] value was between 0.60 and 1.00) were calculated to test inter-rater reliability of the scores obtained by the rating scale. Findings provided evidence for the reliability and the validity of the ABI rating scale. ABI lesson plan template and ABI rating scale developed for the assessment and evaluation of ABI lesson plans and subsequent teaching practices are provided to the readers. Contributions to the field are discussed.