Maybe IQ scores are rising because they are becoming more important in society. The article says people who have attended school less do not score as well. So

Maybe IQ scores are rising because they are becoming more important in society. The article says people who have attended school less do not score as well. So, if IQ has permeated the school system as an important metric, it makes sense that children will be trained to do well on IQ tests. As it is, the article states the IQ increase correlates well with better education, health, and family structure. Also, at the end of the article, it states there are indications the IQ increase has stopped, and may be reversing, in the Western world.