You are what you know.
A contemporary view of intelligence finds that it is the sum of two factors:
G(f) is fluid intelligence- the size of your working memory, how ‘fast you think’ etc.
G(c) is concrete intelligence- a measure of how much factual information you have acquired.
Learning more information then is the key to greater intelligence.
Hart and Risley (1995) found that children in non-working households heard, on average, 616 words per hour, while children from professional families heard 2153. By the age of three this totaled a difference of 30 million words. Less well off children are exposed to fewer concepts- and develop less concrete intelligence.
Research into memory and cognitive neuroscience has soundly shown that the learning of new material is much more efficient if you already know a body of linked material.
Eric Hanushek’s work suggests that a good teacher can get 1.5 years of learning growth in one year, a bad teacher 0.5. Theconsequences of a bad teacher for a number of years in a row can be devastating. Note that many of our most challenging schools struggle to attract good teachers.
Finally, we know which classroom practices most enhance learning and achievement. We have a well-developed science of learning- but you’ll have to look very hard to find proof of this in our schools. It’s long overdue that schools, classrooms and teachers applied what works, and the folk pedagogy and traditions that guide our educational institutions were replaced by evidence-driven practice.