Abstract
The study aimed to unravel the degree to which scientific and engineering practices complied with the NGSS (Next Generation Science Standards) were present in the performance of physics teachers at the secondary stage in Taif city, Saudi Arabia. The study also sought to identify the effect of the qualification and years of experience variables on the degree to which the NGSS-aligned practices were present in the performance of physics teachers. The study adopted a mixed method in applying a closed-ended questionnaire and an interview. The questionnaire comprised 44 indicators and was applied to (49) teachers who were randomly selected. The interview was applied to (6) education supervisors who were purposively selected. The results revealed that the following five practices: "asking questions and identifying problems"; "obtaining, evaluating, and communicating information"; "planning and carrying out investigations"; "analyzing and interpreting data"; and "involvement with proofs and evidence" all rated medium. The three practices, "interpretation and solutions design"; "developing and using models"; and "using mathematics and computational thinking" all rated weak. Data analysis of education supervisors' interviews revealed that their opinions were, to an extent, concordant with the questionnaire findings. The results also revealed that graduate teachers exhibited a higher level of these practices than the teachers with just BS degrees while years of experience, as a variable, had no significant difference in teachers' use of these practices. It was concluded that teachers of physics need to reconsider their teaching practices to be aligned with NGSS. This study can be a contribution to teachers' professional development efforts that target the alignment of science instruction with the NGSS.