For more information concerning learning contracts check out the following resources.
Smutny, J., Walker, S., & Meckstroth, E. (1997). Teaching Young Gifted Children in the Regular Classroom. Free Spirit Publishing Inc.
Brandt, R. Ed. (1994). Challenging the Gifted In the Regular Classroom. Association for Supervision and Curriculum Development.
Tomlinson, C. (1995). How to Differentiate Instruction in Mixed-Ability Classrooms. Association for Supervision and Curriculumm Development.
