摘要：AbstractConjecturing is viewed as a creative work, how to evaluate the quality of student's conjectures in modifying premises and conclusions on the given tasks is our concern in this study. Results showed that 46% of 84 eighth graders and 43% of 91 ninth graders generated conjectures of good quality ingeometrical parallelcontent, and 24% of 84 eighth graders and 17% of 91 ninth graders generated conjectures of good quality infactors of an integercontent. Interview data showed that students who generated conjectures of good quality used bothexamplesandlogical statusesto guide their thinking.
