Obligations: Amounts of orders placed, contracts awarded, services received, or similar legally binding commitments made by federal agencies during a given period that will require outlays during the same or some future period.

Occupational concentrator: Public high school graduate who earns 3.0 or more credits in a single occupational program area.

Occupational education: Vocational education programs that prepare students for a specific occupation or cluster of occupations, including agriculture, business, marketing, health care, protective services, trade and industrial, technology, food service, child care, and personal and other services programs. Also called occupationally specific education or specific labor market preparation.

Occupational investor: Public high school graduate who earns 3.0 or more credits in occupational education.

Odds ratio: Odds is the ratio of success to failure in probability calculation. Odds ratio is the ratio of one odds to another.

Ordinality and sequence: As used in the Early Childhood Longitudinal Study, Kindergarten Class of 1998 (ECLS–K), this mathematics skill is an understanding of the relative position of objects.

Organization for Economic Cooperation and Development (OECD): The OECD is an organization of 30 nations whose purpose is to promote trade and economic growth in both member and nonmember nations. OECD’s activities cover almost all aspects of economic and social policy. The current member countries include Australia, Austria, Belgium, Canada, the Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Japan, Korea, Luxembourg, Mexico, the Netherlands, New Zealand, Norway, Poland, Portugal, the Slovak Republic, Spain, Sweden, Switzerland, Turkey, the United Kingdom, and the United States.

Orthopedic impairments: A severe orthopedic impairment that adversely affects a child’s educational performance. The term includes impairments caused by congenital anomaly (e.g., clubfoot, absence of some member, etc.); impairments caused by disease (e.g., poliomyelitis, bone tuberculosis, etc.); and impairments from other causes (e.g., cerebral palsy, amputations, and fractures or burns that cause contractures).

Other disabilities: Developmental disabilities including mental retardation, emotional disturbance, hearing impairments, orthopedic impairments, other health impairments, visual impairments, multiple disabilities, deaf-blindness, autism, traumatic brain injury, and developmental delay. There is a wide range of disabilities included in this category; they are included in indicator 8 to represent cases contributing to the total not otherwise presented in the graph due to their relatively low prevalence in the population.

Other expenditures: Other than support services and capital outlay, the sum of all other current fund expenditures for community services, nonpublic school programs, adult education, community colleges, interest on school debt, and other expenditures.

Other incidents: Incidents including possession of a firearm or explosive device, possession of a knife or sharp object, distribution, possession, or use of illegal drugs or alcohol, and vandalism.

Other religious school: A private school that is affiliated with an organized religion or denomination other than Roman Catholicism or that has a religious orientation other than Catholicism in its operation and curriculum.

Other support services staff (elementary and secondary school): All staff not reported in other categories. This group includes media personnel, social workers, data processors, health maintenance workers, bus drivers, security, cafeteria workers, and other staff.

Outlays: The value of checks issued, interest accrued on the public debt, or other payments made, net of refunds and reimbursements.