For almost a century, researchers have studied creative imagination, most typically that of children. This article reports on a study of the development of creative imagination of Chinese youths and its relation to the educational environment. Data consisted of 4,162 students from grades 4 through 12. Findings showed that students' creative imagination increased as the grade in school increased from grades 4 through 11, but decreased slightly at grade 12. Students' creative imagination was lower in elementary school than that in middle school. The pace of development was also different in different stages. In different grades, youths used different ways to express their imagination. Students of "excellent" academic performance had the highest creative imagination, followed by students of "fairly good", "medium" and "poor" academic performance. Student-centred teaching methods were associated with higher creative imagination. Students whose teachers had a more supportive attitude showed better creative imagination. Finally, taking part in science-related competitions and frequently visiting science venues were related to the development of students' creative imagination. Some implications and recommendations for development of students' creative imagination are also proposed. (Contains 4 tables and 2 figures.)