発達障害が不登校の要因として重要であることについては，近年注目されるようになり，要因，きっかけ，予後についても研究が行われている．発達障害であるが知的に高い子どもたちについても，不登校の割合が多く認められることは知られていない．2Eすなわちtwice-exceptional（二重に特別な）とは，「知的に高い（

This research examines the RTI（Response to Intervention）model for the gifted，which is a new practical framework for gifted education in the U.S. and clarifies the relation between its characteristics and those of other gifted education programs.

In recent years，the RTI model for the gifted has been disseminated as an RTI application model，which is different from an ordinary RTI model developed as a diagnostic and teaching system for children with learning disabilities. The teaching contents and curriculum in the RTI model for the gifted requires the use of pre-existing gifted education programs as a precondition. Hence，this paper examines how these existing gifted education programs are positioned within the framework of the RTI model for the gifted，which is characterized by a multi-tiered structure， and what kind of changes they bring about in the imparting of gifted education.

In particular，the contents of gifted education in the U.S. were classified and sorted according to two curriculum types: acceleration and enrichment. Furthermore，their incorporation into each tier in Utah’s Four-Tier Model（the RTI model for the gifted in the state of Utah）was examined. The results indicated that in the acceleration program，various acceleration measures and systems in traditional gifted education were utilized at each level and radical acceleration specialized for gifted children was conducted in fourth tier. In contrast，in enrichment programs， enrichment education targeting all students was conducted in １st tier normal education while a more advanced enrichment education was conducted in the higher tier simultaneously. In both cases，specialization and differences in teaching based on children’s interests，attention，learning style，and level of understanding were emphasized，with the forms of teaching and the established plans changing on the basis of students’ abilities.

Further，the Schoolwide Enrichment Model，which is a representative curriculum in gifted education，was examined to investigate and explore how existing curriculum models can be adapted within the RTI framework. The characteristics of curriculum models that could be easily adapted to RTI were also considered. The results showed that curriculum models such as the Schoolwide Enrichment Model，which boasts a multi-tier and multi-stage structured curriculum and in which the teaching level and contents gradually change to match students’ abilities and needs，have an affinity to the RTI framework.

Lastly，the challenges in implementing gifted education programs in the RTI model for the gifted were examined to identify the necessity of enriching the implementation of the core curriculum，forms of teaching，and plans that were suitable for implementing the program as well as for training teachers regarding gifted education.

This paper examined U-STARS~PLUS (Using Science, Talents, and Abilities to Recognize Students ~ Promoting Learning for Underrepresented Students), a gifted and talented education curriculum model recently developed in the United States, focusing on efforts to assuage racial discrimination in gifted and talented education from the viewpoint of curriculum development.

In discussions that use the development of U-STARS~PLUS as a background, I determined the current state of access inequality in gifted and talented education programs in the United States; this enabled me to confirm that the participation of minority children, mostly black and Hispanic, in gifted and talented education programs is at an unusually lower rate compared with white children. Among the factors that have particularly caused this issue to come to the fore in recent years, I identified an increasing number of racial minorities in public schools, as well as the actualization of inequality due to the expansion of gifted and talented education since the 1980s and the recognition of unfair access to gifted and talented education programs as a serious policy issue in gifted and talented education.

Subsequently, I examined the shared characteristics of curriculum models intended to expand minority access, indicating that minority underrepresentation is an issue of unfairness exclusively while acknowledging talented children. The results revealed that such curriculum models were expanded models that targeted not only children formally recognized as gifted but also all other children; further, it was also observed that most of these models had been developed to enable the gradual implementation of advanced investigational activities for determining children’s abilities.

Additionally, I outlined the development process and basic structure of U-STARS~PLUS, which was developed through funding from the federal government. It is indicated that U-STARS~PLUS places special emphasis on the systematic observation of children with potential ability, using Teacher’s Observation of Potential in Students (TOPS) to remove teacher bias against minorities and incorporating TOPS into the RTI model for the gifted, which is a new practical framework for gifted and talented education to ensure that U-STARS~PLUS develops into a more effective curriculum model.

Finally, I examined the effectiveness of TOPS based on the results of the inspection of the U-STARS~PLUS Project, which was implemented over 5 years from 2003 to 2008 and verified its results by fairly recognizing latent abilities in minority children. Consequently, I considered issues in the implementation of U-STARS~PLUS, which emphasizes finding solutions to the underrepresentation of minority students in gifted education.