Differentiation can mean the following:

Instruction: The TIP Database - Summaries of 50 major theories of learning and instruction. These theories can also be accessed by learning domains and concepts.
Acceleration: Should Gifted Students Be Grade-Advanced? - Covers reasons for and against advancement.
Basic Educational Options for Gifted Students in Schools - Article by J.VanTassel-Baska discusses the different curriculum options available to schools to address the needs of the gifted.
Curriculum Differentiation - Curriculum Differentiation as an educational provision for gifted students.
Meta Description: [ Provides an overview of how mentoring can be introduced into a school's educational provisions ]
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David Baird's Gifted Children Web Site - Issues of teaching and parenting a gifted child, projects and activities, designing an educational program for the gifted, and 10 tips for beginning teachers.
Differentiating Curriculum for Gifted Students. - ERIC Digest #E510.
Early Entrance College Programs - Guide and comparison of early entrance college programs in the USA. These programs provide opportunities for gifted youngsters to enter college years ahead of time.
GATE/AP ChatBoard - discussion board for discussions related to Gifted and Talented Education/Advanced Placement.
Meeting the Needs of Gifted Students - How to meet the needs of the gifted in upper primary grades.
National Research Center on the Gifted and Talented (Javits Center) - Describes the goals and objectives of Javits Center plus current projects which include successful classroom practices, curriculum compacting, cooperative learning.
Meta Description: [ The Javits Center conducts research on the most effective ways of identifying, nurturing, and developing the many talents of students from diverse ethnic and socioeconomic backgrounds and other related research on the meeting needs of all students. ]
Successful Strategies for Teaching Gifted Learners - Tips for teachers of an all-inclusive classroom.
Teachers Resources - Links on issues associated with highly gifted children and on general gifted education.