The resource guide on developing and/or refining extended school year (ESY) services is intended for local educational agencies in the State of Washington. Part I of the guide describes legal and educational issues, district policy development, eligibility factors, and includes one district's ESY data collection system. Section I presents a brief overview of the current legal requirements that must be considered, reviews major litigation and Office for Civil Rights requirements. Also included are a statement on state and district responsibilities and a discussion of ESY eligibility considerations. Section II offers information on ESY policy considerations and staff responsibilities for developing and implementing ESY services including the function of the multidisciplinary team in the ESY decision making process. Section III provides a comprehensive review of one model for determining ESY service eligibility. Policies and procedures developed by the Highline School District to determine ESY service eligibility are outlined including planning, training, and implementation sequences. A sample action plan details steps for implementing an ESY service eligibility model. The final section includes a reference list and appended material including legislative bases and ESY Data Collection Forms. (DB)