Continued education
The educational duration is positively correlated with intelligence testing results. It is possible to interpret this correlation in one of two ways: Students with a greater propensity for intelligence go on to complete more education, or a longer education increases intelligence.
Any form of education is essential for the growth of human intelligence. Over 600,000 participants were examined in a review of research on IQ and education to find out how education affected IQ scores. For every additional year of formal education, participants' IQs increased by one to five points, according to research. The most reliable, strong, and long-lasting strategy for increasing intelligence that has been discovered so far seems to be education.