This multiple case study examined the phenomenon of gifted student underachievement, using creative productivity (Type III enrichment in Renzulli's Enrichment Triad Model) as a systematic intervention for reversing the underachievement pattern. Twelve teachers selected 17 underachieving students (ages 8 to 13) as subjects. The study first identified a variety of factors contributing to underachievement of high ability students, including emotional issues, social and behavioral problems, the lack of an appropriate curriculum, and learning and self-regulation difficulties. The study's major finding was that almost all the students made gains in achievement, attitude, or behavior during the year of or the year following the intervention. Students were differentially affected by such aspects as the relationship with the teacher and the learning of self-regulation strategies. Several teacher behaviors emerged as crucial to student success, including: (1) taking time to get to know the student; (2) focusing on positive traits of the student; (3) understanding their role as facilitator; (4) applying the role of teacher as researcher; and (5) conveying a belief in the students' abilities. Appended are a sample management plan and a sample page from a student product. (Contains 70 references.) (DB)