Two experiments were carried out in an incidental learning paradigm. In Experiment I, 35 sixth-graders and 22 undergraduates were asked to rate the sematic congruity of each target with sentence frame followed by free and cued recall tests. Free recall performance of targets was better in syntactic-congruous sentence frames than in syntactic-incongruous ones in both groups. Sentences containing an associate of each target had led to better cued recall performance than those without. In Experiment II, 33 sixth-graders and 23 undergraduates were asked to rate the semantic congruity of each target with sentence frame followed by free recall, recognition and cued recall tests. Each target was referred to have been elaborated when the word in its sentence frame was hit in recognition test. In sixth graders free recall performance of the elaborated targets was seen better in sentences containing their associate, but the difference between the two sentences was not observed in the undergraduates. These results were interpreted as showing a developmental difference in the effect of aid for integration of targets into cognitive structure.