Extended School Year (ESY) services are designed to support a student with a disability as documented under the Individuals with Disabilities Education Act (IDEA) to maintain the academic, social/behavioral, communication, or other skills that they have learned as part of their Individualized Education Program (IEP) or Section 504 accommodation plan.

In order for a student to receive ESY services, the student must have evidenced substantial regression and recoupment issues during the previous IEP year and/or there is evidence of emerging skills which are often referred to as "breakthrough" skills. The focus of the services provided to the student as part of an ESY program are generally not upon learning new skills or "catching up" to grade level, but rather to provide practice to maintain previously acquired or learned skills.

In some cases ESY is focused on continuing education for students whose rate of progress is insufficient to enable effective progress during the regular school year. If a student has received ESY services in previous years the student may not be eligible in future years as determinations for eligibility of ESY services are made annually by the IEP or 504 plan (which includes the parent and student of age 16 or older.