A condition that interferes with a student's ability to learn. Even the definition of this term is controversial. The Individuals with Disabilities Education Act amended in 1997 defines a specific learning disability as "a disorder in one or more of the basic psychological processes involved in understanding or in using language, spoken or written, which disorder may manifest itself in imperfect ability to listen, think, read, write, spell, or do mathematical calculations. Such term may include such conditions as perceptual disabilities, brain injury, minimal brain dysfunction, dyslexia, and developmental aphasia." Children not included under this provision include those who have learning problems which are "primarily the result of visual, hearing, or motor disabilities, of mental retardation, of emotional disturbance, or of environmental, cultural, or economic disadvantage." Schooling that helps students understand and relate to cultural, ethnic, and other diversity, including religion, language, gender, age, and socioeconomic, mental, and physical differences. Multiculturalism is intended to encourage people to work together and to celebrate differences, not to be separated by them. However, the field itself is controversial. Refers to curriculum in more than one discipline or subject area. People may use this term and related ones differently, but, in general, a multidisciplinary curriculum is one in which the same topic (e.g., harmony) is studied from the viewpoint of more than one discipline (e.g., music, history, and literature). For example, students may study weather using a variety of disciplines. They might study the current science behind measuring air pressure, learn about the history of weather prediction, and read and write poetry about weather. A theory of intelligence developed in the 1980s by Howard Gardner, professor of education at Harvard University. Gardner defines intelligence broadly as "the capacity to solve problems or fashion products that are valued in one or more cultural setting." He originally identified seven intelligences: linguistic, logical-mathematical, musical, spatial, bodily-kinesthetic, interpersonal, and intrapersonal. He later suggested the existence of several others, including naturalist, spiritual, and existential. Everyone has all the intelligences, but in different proportions. An approach to schooling that makes outcomes—intended results—the key factor in planning and creating educational experiences. In the 1990s, some states and local school systems announced plans to drop some conventional requirements, such as using Carnegie units to measure the amount of learning, and instead to organize instruction around intended outcomes, such as teaching students to be "collaborative workers." Adherents said their intention was to emphasize actual student accomplishment (outcomes) rather than traditional measures of school quality, such as course offerings and teacher qualifications (inputs). They said that the amount of time spent learning and other factors, such as what the student does in order to learn, should depend on the outcome to be achieved. In conventional schooling, they said, time is fixed and outcomes are variable. Instead, outcomes should be fixed and time should be variable.