As an European, I did never have any IQ test, nor I know anybody who (to my knowledge) was ever administered an IQ test. I looked at some fac-simile IQ tests on the internet, expecially Raven's matrices.
When I began to read online blogs from the United States, I started to see references to the concept of IQ. I am very confused by the fact that the IQ score seems to be treated as a stable, intrinsic charachteristic of an individual (like the height or the visual acuity).
When you costantly practice some task, you usually become better at that task. I imagine that there exists a finite number of ideas required to solve Raven matrices: even when someone invents new Raven matrices for making new IQ tests, he will do so by remixing the ideas used for previous Raven matrices, because -as Cardano said- "there is practically no new idea which one may bring forward".
The IQ score is the result of an exam, much like school grades. But it is generally understood that school grades are influenced by how much effort you put in the preparation for the exam, by how much your family cares for your grades, and so on. I expect school grades to be fairly correlated to income, or to other mesures of "success".
In a hypothetical society in which all children had to learn chess, and being bad at chess was regarded as a shame, I guess that the ELO chess ratings of 17 year olds would be highly correlated with later achievements. Are IQ tests the only exception to the rule that your grade in an exam is influenced by how much you prepare for that exam? Is there a sense in which IQ is a more "intrinsic" quantity than, for example, the AP exam score, or the ELO chess rating?
I love the social sciences, but they tend to tell you more about the people studying them then they do about the actual subjects they study. I'm a believer that much of the data in the Social Sciences would benefit from reexamination using recalibrated metrics, as the political shifts in the world of the last 50 years have caused seismic shifts in the ways data is collected, organized, and interpreted. I've got some ideas of major areas of the Social Sciences which need to be reconsidered, as they have significantly impacted legislation in ways that have caused almost immeasurable suffering around the world IMO.
IQ is one of those 'classic' metrics which has in some ways fallen out of favor as being meaningful for large portions of society. I wouldn't go so far as to suggest it is akin to phrenology, but what exactly it measures in relation to practical ideas of intelligence is in debate. Short of diagnosing potential Developmental Disorders, they are part of a battery of tests these days, as by themselves IQ test results don't tell much useful information.