Within the framework of Pascual-Leone's Theory of Constructive Operators (TCO), 252 Zulu-speaking children in the 7-8 , 9-10 and 11-12 age-groups were tested four times on the FIT RAC 794, a measure of mental capacity or !i-power. Two hypotheses were investigated: (i) A "local" hypothesis (related to the fact that many black South African schoolchildren appear to struggle at school) was that 'all children have the same A-power. Performance differences are explained in terms of different learning experiences, which give rise to different repertoires of executive structures responsible for allocating M-power. It was predicted that on Trial 1 of the FIT children would underperform, but that with repeated exposure to the task they would develop the executives necessary for success. (ii) A "general" hypothesis sought to test the TCO's theoretical prediction that there is an age-linked developmental ceiling on performance, and that in spite of over-learning children will not perform beyond their age -determined M-power. As predicted the children underperformed on Trial 1. They reached criterion on Tri a1 2 and then overperformed on Tri a1 3 where performance reached a ceiling with no further significant improvement on Trial 4. The fact that chiIdren achieved scores above those predicted by the TCO on Trials 3 and 4 was explained in terms of non-M facilitating factors, developed as the result of over-exposure to the test.

Thesis(M.A.)-University of Natal, Durban, 1985.