Three classes: one fourth grade class, one fifth grade class, and one sixth grade class.
This article is from the National Association for Gifted Children: https://www.nagc.org
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Why Are Gifted Programs Needed?
Gifted and talented students and those with high abilities need gifted education programs that will challenge them in regular classroom settings and enrichment and accelerated programs to enable them to make continuous progress in school.
- According to a recent report on high-achieving students, more than 7 in 10 teachers of these students surveyed noted that their brightest students were not challenged or given a chance to “thrive” in their classrooms.  Additionally, gifted students need gifted programming in many cases because the “general education program is not yet ready to meet the needs of gifted students” (p. 9) due to lack of general educators’ training in gifted education and the pressure classroom teachers face to raise the performance of their struggling students. 
- It’s more than just giving students a challenge in classrooms: Gifted programming positively influences students’ futures. Several longitudinal studies have shown that gifted programs have a positive effect on students’ post-secondary plans. For example, studies found that 320 gifted students identified during adolescence who received services through the secondary level pursued doctoral degrees at more than 50X the base rate expectations.  In a follow-up report on the same study participants at age 38, 203 participants, or 63%, reported holding advanced terminal degrees (master’s and above). Of these, 142 (44%) held doctoral degrees and 8 of these 142 had more than one doctoral degree. As a benchmark for this accomplishment, the authors of this study compared these rates to the general U.S. population, noting that only approximately 2% of the general population held a doctoral degree according to the 2010 U.S. Census. 
- Additionally, in a study looking at gifted students who participated in talent development through competitions, the researchers reported a long-term impact on these students’ postsecondary achievements, with 52% of the 345 students who participated having earned doctoral degrees. 
- Further benefits of gifted programs have been shown to include that students who had participated in gifted programs maintained their interests over time and stayed involved in creative productive work after they finished college and graduate school. 
- A sample of 2,409 intellectually talented adolescents (top 1%) who were assessed on the SAT by age 13, and provided services through a talent search program, was tracked longitudinally for more than 25 years. Their creative accomplishments, with particular emphasis on literary achievement and scientific-technical innovation, were examined and results showed that distinct ability patterns identified by age 13 foreshadowed creative accomplishments in middle age. Among the sample, participants had earned 817 patents and published 93 books, one had been awarded the Fields Medal in mathematics, and another had won the John Bates Clark Medal for the most outstanding economist under 40. 
1 Loveless, T., Farkas, S., & Duffett, A. (2008). High-achieving students in the era of NCLB. Washington, DC: Thomas B. Fordham Institute.
2 Hertberg-Davis, H. L., & Callahan, C. M. (2013). Introduction. In H. L. Hertberg-Davis & C. M. Callahan (Eds.), Fundamentals of gifted education (pp. 1–10). New York, NY: Routledge.
3 Lubinski, D., Webb, R. M., Morelock, M. J., & Benbow, C. P. (2001). Top 1 in 10,000: A 10 year follow-up of the profoundly gifted. Journal of Applied Psychology, 4, 718–729.
4 Kell, H. J., Lubinski, D., & Benbow, C. P. (2013). Who rises to the top? Early indicators. Psychological Science, 24, 648–659.
5 Campbell, J. R., & Walberg, H. J. (2011). Olympiad studies: Competitions provide alternatives to developing talents that serve national interests. Roeper Review, 33, 8–17.
6 Westberg, K. L. (1999, Summer). What happens to young, creative producers? NAGC: Creativity and Curriculum Division Newsletter, 3, 13–16.
7 Park, G., Lubinski, D., & Benbow, C. P. (2007) Contrasting intellectual patterns predict creativity in the arts and sciences: Tracking intellectually precocious youth over 25 years. Psychological Science, 18, 948–995.
- See more at: https://www.nagc.org/resources-publications/gifted-education-practices/why-are-gifted-programs-needed#sthash.uie5dMpD.dpuf