The aim of this paper was to test the hypothesis of a context dependence of number
processing in children. Fifth-graders were given two numbers presented successively
on screen through a self-presentation procedure after being asked either to add or
subtract or compare them. We considered the self-presentation time of the first
number as reflecting the complexity of the encoding for a given planned processing.
In line with Dehaeneâeuro?s triple-code model, self-presentation times were longer for
additions and subtractions than for comparisons with two-digit numbers. Alternative
interpretations of these results in terms of more cognitive effort or more
mental preparation in the case of addition and subtraction than comparison are
discussed and ruled out.