“…We already know that the curriculum standards place great emphasis on the importance of problem posing; that there is much research showing the positive effects of mathematical problem posing on students' interest in mathematics and creativity in mathematics, as well as on self-efficacy and problem solving; and that there are many specific strategies or techniques for helping students to pose (better) mathematical problems, such as the strategies of "what-if-not" [8], chaining, systematic variation, and symmetry [9]. There are also studies on the process, phases, or stages of problem posing, such as Cruz's model of process (educative needs, goal, problem formulation, problem solving, and problem improving) [10]; the five phases (setup, transformation, formulation, evaluation, and final assessment) [11]; the five types of activities (situation analysis, variation, generation, problem solving, and evaluation) [12]; and, most recently, Cai's problem-posing task-based instructional model [13]. However, there is still a need to unfold the following directions: the design of problem-posing tasks in mathematics textbooks; teachers' design of problem-posing-based lessons; teachers' implementation of problem posing in mathematics classrooms; and the assessment of problem posing in teachers' teaching and students' learning, teachers' problem-posing beliefs and performance, students' problem-posing performance and influencing factors, and how problem posing promotes mathematics.…”