Ability and achievement are not traits: they are relations. Mistaking traits for relations has a history even in science (our understanding of gravity). This mistake is possibly responsible for the lackluster performance of the results of our educational research when we have tried to use it to inform policy. It is particularly troublesome for interventions that target "children at risk." The paper provides a quasi-formal outline of achievement as a relation and it then uses the outline to explain some problematic research findings.