The authors hightlight the following point at the beginning of the article:
But they then go on to mention many irrelevant things.
The above point clearly indicates that parental involment at home from birth to elementary shool is the most important factor for the kids who go get ahead. Richer parents don’t pay for tutors, enroll kids in robotics class, push them to solve obscure math problems when the kids are in preschools and elementary schools.
There are some advantage for the kids who are born in richer families. But wealth is not the sole factor that influences education. The “middle class” kids in some poor countries are poorer than most kids in the poor families in the US. Their parents’ income is less than $2,000, $3,000 per year and they don’t eat three full meals each day. However, they are not totally shut out in education.