"The term IQ, or Intelligence Quotient,
generally describes a score on a test that rates the subject’s
cognitive ability as compared to the general population. IQ tests use a
standardized scale with 100 as the median score. On most tests, a score
between 90 and 110, or the median plus or minus 10, indicates average
intelligence. A score above 130 indicates exceptional intelligence and
a score below 70 may indicate mental retardation. Like their
predecessors, modern tests do take in to account the age of a child
when determining an IQ score. Children are graded relative to the
population at their developmental level.