Fairness issues
Some students may not score 85% or higher in any subject area. All students, however, benefit from pursuing their interests by utilizing their strengths. If everyone gets an opportunity at least once a week to focus on something that is special to them, then no one should complain about not getting a chance to work on projects. Project time may last anywhere from one hour to all day.
Housekeeping hints
Keep a Work in Progress folder for each student to store his or her projects while not in use. Do not use a student's earned time in one area to remediate skills in another area. Allow students to pursue their passions with the time they have earned. You might be surprised by how much transfer of skills there is from an area of interest to a less favorite subject when people are allowed to learn more about something in which they already excel.
Behavior problems are a consequence of two sources: Either the curriculum is inappropriate or the structure of the environment is inappropriate. Students pursuing their passionate interests in an environment conducive to learning will not become behavioral problems. They will become educated.
Good luck and have fun!
References
Renzulli, J.S. and Reis, S.M. (1991) "The schoolwide enrichment model: A comprehensive plan for the development of creative productivity." In N. Colangelo & G. Davis (Eds.), Handbook for Gifted Education (pp. 111-141). Allyn & Bacon: Boston, MA.
Weinbrenner, S. (1992). Teaching Gifted Kids in the Regular Classroom. Free Spirit Publishing: Minneapolis, MN.
