Abstraction is a pivotal concept in computer science (CS); it is extensively utilized for various purposes such as problem simplification and algorithm design. Often considered the most important mental tool for computer scientists, abstraction is a key element in CS education and curricula. However, teaching CS abstraction is known to be difficult. One of the instructional methods offered in the literature to promote abstraction is pattern-oriented instruction (POI), which relies on algorithmic patterns and uses them as organizing principles and a central problem-solving strategy. Research has shown that using pattern-oriented instruction supports students’ abstraction abilities; however, we claim that POI alone may not be sufficient and therefore deeper exploration is required to understand the relations between employing POI, teaching abstraction and developing abstraction skills. In this qualitative study, we thoroughly analyzed the teaching approaches of eight high-school CS teachers, focusing on their use of POI and how they teach abstraction (both their perceived and actual teaching approaches). The results suggest that although POI may support the perception of the teachers as promoting abstraction, its actual implementation may not fully align with this purpose.