While it is very hard to separate the effects of nature (genes) and nurture (environment and effort), a wide range of studies show that over half of the variance in personality traits and mental abilities can be explained by genetic factors and attributed to heredity. While I have no doubt that genes influence our abilities, I have also read a wide range of books and studies on neuroplasticity, or the way our brains are shaped by our experiences and environment, leading me to believe that excellence in any field (academic or non-academic) tends to be a result not just of genes but of sustained effort over time.
So there you have it: what's the key to academic success (or any kind of success for that matter)? It's sustained effort in a particular field or area over time.
In other words, a student who has been immersed in a language-rich environment since birth and has read extensively all through her elementary years will be far more likely to excel in English in high school than a student who didn't read much in the early years.
Similarly, a student who has spent time on math every day since she was four will be far better equipped to do high school math as a teenager. When I asked my Korean student Ha Young whether she thought she was "naturally talented" at math, she replied, "Well, I've just done so much math that all that practice has made me good at it. I think it's hard to know whether I have any natural talent. All I do know is that math is very easy for me because I spent so much time as a young child practicing, and I have always spent time on math."
Just as excelling in a field may be partially due to genes and partially due to sustained effort and exposure in that area over time, struggling in a field may also be due to a combination of genes and a lack of sustained effort and exposure in that area over time.
(Extracted from #Beyond The Tiger Mom, p. 156, 157; footnotes/studies included in the book.)
The implications are easy. Help kids cultivate strong basic skills in reading, writing, and math right from the get-go.