This study aimed at developing a scale, Technological Pedagogical Content Knowledge-Thinking Tools (TPACK-TT), and exploring Chinese in-service primary teachers’ TPACK concerning the use of thinking tools. By revising a previous Chinese TPACK survey and validating with exploratory factor analysis, a six-component (i.e., TK-TT, PK, CK, TPK-TT, PCK, and TPCK-TT) scale with 31 items was developed. Research data gathered from 204 primary teachers from a variety of schools revealed that teachers with different educational backgrounds and various ov...