Numerous persons have suggested that instruction should match the developmental level of the learner. Are “concrete operational” college students developmentally the same as “concrete operational” seventh grade students thus in need of identical instruction? Matched concrete operational seventh grade and college students were given identical classroom instruction in probabilistic and correlational reasoning. The college students performed significantly better on posttest measures which appeared to require greater processing of information while significant differences did not exist on less difficult items. Level of cognitive development, field independence, and fluid intelligence correlated moderately with posttest performance for the seventh grade students. Field independence and fluid intelligence correlated moderately with posttest performance for the college students but not pretest knowledge of specific biological concepts and cognitive level. It was concluded that college students are more responsive to instruction due either to (1) greater amount of experience or (2) greater information processing capacity. Implications for science teaching are discussed.