Does Instrumental Enrichment Work

Summary Israeli and American research on IE was reviewed, indicating effect‐sizes over a two‐year intervention period on tests of crystallised intelligence and achievement of the order of three months of mental age (MA) only. A small‐scale study (NE= 10; NC=10) was set up in an ESN(M) school under optimum conditions to test the effect of IE on the additional parameters of Piagetian Operations and of Phase, the Feuerstein information‐processing model. Effect sizes'of 1.22a on Operations, and 1.07a on Phase were reported, together with 0.76a on deficient cognitive functions as tested by Feuerstein's Learning Potential Assessment Device (LPAD). In MA terms, these sizes corresponded to 20 months differential gain on Operations over a 20 month period, and 12 months differential gain on Phase over a 12#fr1/2> month pre to post‐test period. The gain on cognitive functions was accompanied by an increase in the zone of proximal development, as tested by LPA, of 1 years. It was concluded that IE affects fluid intel...