As James A. Kulik of the University of Michigan reported in the
Handbook of Gifted Education (2003), “On the basis of site visits, experts have concluded that untracking brings no guarantee of high-quality instruction for everyone but may instead lead all to a common level of educational mediocrity.”
Multiple intelligence theory is only the latest rationale for acting as if most children don’t differ much in learning ability. An older approach, still widely embraced, is to accept IQ as a concept but act as if differences in IQ don’t make much difference in the classroom. Education textbooks and journals in this vein speak only of “exceptional” versus “regular” students. So-called regular students are those who score between the upper threshold for mental retardation (IQ 70) and the lower threshold for giftedness (IQ 130). That continuum includes 95 percent of students. A closer look at differences in intellectual functioning across the 60-point range illustrates how different educability actually is, even among the supposedly average.
For example, individuals with IQs between 70 and 80 (but still above the threshold for mild retardation) require instruction that is highly structured, detailed, concrete, well sequenced, omits no intermediate steps, and links to what the individuals already know. They often need one-to-one supervision and hands-on practice to learn even simple procedures. As specialists in adult education explain, the material to be learned must be stripped of all nonessentials, including theoretical principles, and require only simple inferences. Any information, written or spoken, must be presented in small pieces with clear introductions and simple vocabulary.
Because people with IQs below 80 (the 10th percentile) are difficult to train, federal law bars their induction into the military.
Successively higher IQs are associated with better odds of learning readily from more demanding forms of instruction, learning more independently, and mastering increasingly abstract and multifaceted material.
Individuals of average IQ (100) can master relatively large bodies of written and spoken knowledge and procedure, especially when it is presented to them in an organized manner that allows them practice and provides feedback. By IQ 120, individuals are more self-instructing and better able to develop and organize knowledge on their own. The “complete” instruction that is most helpful for low-g learners is dysfunctional for these high-g individuals. The
latter easily fill in gaps in instruction on their own and benefit most from abstract, self-directed, incomplete instruction that allows them to assemble new knowledge and reassemble old knowledge in idiosyncratic ways. But such forms of instruction are dysfunctional for low-g learners, who are more likely to be confused than stimulated by its incompleteness, abstractness, and
requirements for self-direction.
As any teacher will attest, many other things besides g-level affect children’s learning—illness, incentives, peer pressure, conscientiousness, parental support, familiarity with the language of instruction, and more. For these and other reasons, high g does not guarantee success—or low g guarantee failure. There’s no
question, however, that higher levels of g constitute a constant tailwind and lower levels a persistent headwind in cognitively demanding settings such as schools.
Perhaps most important, g level affects what students are likely to learn with a reasonable expenditure of time and effort. Textbooks on instructional strategies rightly treat time as a precious commodity to be jealously guarded and wisely spent, and they note that “slow” students often need much more of it than others to learn the same material. Instruction must therefore be more tightly focused on what is most essential for them to learn.
