There have been several decades of research claiming to support the hypothesis that atheists are more intelligent than Christians. However, there is a growing consensus that this research is not measuring intelligence, which is
controversial in itself, but
greater dependence on intuition rather than logic and reason in thinking and decision-making by the religious (
link)(
link). In addition, there is criticism of the methods used and the interpretation of the results in these, and other, studies of intelligence (
link).
Given the above, some are concluding that appropriate
cognitive training may help in changing the way the religious think (
link). Seems like support for the teaching of
critical thinking skills to me. Albert Einstein agreed:
"The measure of intelligence is the ability to change."