It could be due to the following
reasons...
1. Christian children go to Sunday schools and that is like English
"tuition" or "extra classes".
2. Christianity was brought to Singapore by the British and so,
mostly conducted in English and Singapore schools happen to be
English schools - giving them an advantage (proficiency in the
language). (I think most Christian students are poor in Chinese or
average in Chinese, sort of proving that it is not
super-natural.
3. Christian parents are educated (due to reasons above) and
because the children have educated Children, their children
benefited. If you look at children from non Christian homes but
with highly educated parents, the children will do well or better
than average. (again - nothing super-natural)
4. Christians are quite logical people but their "logic" is skewed,
so that you will not find many cutting edge scientists or
philosophers among Christians. To be able to do cutting edge
science and philosophy, your logic must not be "skewed". You have
to be absolutely crystal clear in your thinking.
Christians believe based on skewed logic but it is still based on
some sort of logic, whereas many non-Christian religious beliefs
are not based on "logic". They are pure beliefs.
Therefore, among believers, Christians have an advantage but among
purely, highly "logical" people, Christians have a disadvantage
because they are "tied" into their system of beliefs and are
therefore restricted or if you want to use an offensive word,
"delusional" in many areas.
