Memory of incidentally learned material was investigated across three developmental levels in immediate and 24-hour delay conditions. First grade, sixth grade, and college students were assigned randomly within developmental level to one of four experimental conditions: Type I immediate, Type I delay, Type II immediate, or Type II delay. In the Type I paradigm, subjects looked at pictures but were given no explicit instruction to remember, and in the Type II paradigm, subjects were instructed to remember specific pictures when shown all stimuli. A four way fixed-factor analysis of variance yielded significant main effects for developmental level, incidental paradigm, and recall condition. Paradigm interacted with recall condition, and significant amounts of incidental learning proved durable for sixth graders and college students. Incidental learning increased with age in both paradigms, suggesting that previously reported divergent developmental trends may not be the result of the type of paradigm, (Author/RD)