Starting in 2019, Taiwan will implement the 12-year basic education. Research into how textbook content responds to competence-based curriculum guidelines is hence urgently critical. This research aims to examine the organization of high school art textbook curriculum. Using content analyses and case studies as methods, this research compares the lesson units on “Line” in the D textbook in the United States and the T and H textbooks in Taiwan. This research uses the revised Bloom’s Taxonomy to analyze the art textbooks’ contents. The findings show that both the T and H textbooks focus on the definition of line. In addition, they use artworks to explain how lines are used in artistic forms and how lines are categorized. More focus, therefore, is on examining artistic knowledge and concepts. On the other hand, D textbook covers a wider range of learning objectives. It starts with examples related to students’ everyday experiences, engaging students in thinking about concepts of lines, and then gradually interweaving art specific content into the curriculum. Our research suggests that Taiwan textbook publishers may consider offering students more opportunities to see how art connects to their everyday experiences. Based on the 12-year basic education curriculum guidelines, this research also suggests textbook writers to incorporate teaching strategies that may foster student’s higher-level thinking and competence in the arts.