We compare the rationality of choice under risk -utility maximization, stochastic dominance, and expected-utility maximization -of students from one of the best universities in the US and one of the best universities in Africa. The US subjects came nearer to consistency with utility maximization and the dominance principle, but there are no differences between the two samples in consistency with expected-utility maximization. A canonical cognitive ability (IQ) test indicates a much larger development gap relative to our tests of economic rationality. The results are robust to the inclusion of controls for non-cognitive abilities and personality traits.JEL Classification Numbers: D01, D03, D81, F61, F63, O12.