All standardized tests tend to be lumped into the same amorphous category, even though different exams obviously, either by design or error, test different attributes and abilities. The SAT and ACT represent the pinnacles of test design, each meticulously crafted over decades to assess much more than the average test taker can imagine. Neither of these exams qualify as IQ tests, but both require the application of various forms of intelligence.
Psychologist Raymond Cattell classified two different types of intelligence: crystallized and fluid.
Crystallized intelligence represents the ability to access and use learned knowledge, skills, and experience. On the SAT & ACT, crystallized intelligence represents, among other things, knowledge of grammar rules, math formulas, and vocabulary.
Fluid intelligence represents the ability to solve think logically, solve problems, identify patterns, and handle novel scenarios. This category also encompasses mental traits like executive function, working memory, and processing speed. On the SAT & ACT, fluid intelligence contributes the logic, abstract reasoning, and critical thinking required to answer many of the most challenging problems in each section.
The right kind of instruction can improve either or both forms of intelligence, but not all education addresses both equally. Researchers from a consortium of New England universities wondered whether schools where students are experiencing high levels of academic success in crystallized intelligence achieve this success by promoting the growth of fluid cognitive abilities. In response, they analyzed the relationships between math and ELA standardized test scores and cognitive ability among nearly 1,400 eight-graders, drawn from a variety of different types of schools in Boston. What did they learn?
1. Cognitive skills and achievement test scores are positively correlated.
2. The perceived quality of a school is positively correlated with standardized test scores.
3. The perceived quality of a school is not correlated with measures of cognitive ability.
4. Thus, variation in schooling influences crystallized but not fluid intelligence.
Studies like these can act like gasoline on the already raging flames of parent anxiety about school districts, classroom instruction, and standardized testing. But further analysis of the study’s caveats offer some relief:
Although school-level educational practices that enhance standardized test scores may not increase broader, fluid cognitive abilities, there is evidence that targeted interventions—both in and out of school— may increase cognitive ability.
In the Boston study, standardized achievement tests served as a proxy for crystallized intelligence, even though many standardized tests challenge fluid intelligence as well. The SAT & ACT certainly tax student intelligence in both categories. So if you’re looking for the kinds of schools and supplemental programs that can lead to success in tests, college, and beyond, take heart; the right kinds of education can foster growth in both crystallized and fluid intelligence. Make sure you seek learning from those who know the difference!