Association for Middle Level Education - "Advisory programs (also called advocacy programs, homebase, teacher-based guidance, advisor-advisee) are predicated on the belief that every young adolescent should have at least one adult at school to act as the student's advocate." This site helps to define and guide the implementation of advisory at the middle level. Research and policy papers are included.
Developmental Designs - During a workshop last spring, I had an opportunity to meet with a principal from central Massachusetts who has been using Developmental Designs resources, trainings and materials to support her staff in implementing an Advisory Program. Developmental Designs is the middle school level of Responsive Classroom. Central aspects of their approach is the daily Circle of Power and teaching and learning routines to gain independence in school and in life.
Educators for Social Responsibility - Locally, ESR provide professional development and resouces to schools and other organizations to increase equity and peace in schools. There is a focus on mediation and conflict resolution in their programing.
Coalition Of Essential Schools - This article from 1990 summarizes an overview of many different Advisory Programs and what distinguishes them. I found it helpful for conceiving what it could be like in 15 minutes a day or 30 minutes per week. Many examples are included in this article but focus mostly on the high school level because of the Coalition's focus on high school.
Education World Resources on what advisory is and why schools would want to implement it.