A study of children's and young adults' retention of words and their presentation modality addressed three issues: (1) how long the modality information is retained, (2) whether children or adults lose it more rapidly, and (3) whether the word or modality information is lost more rapidly. The study consisted of two experiments. In the first, 32 third- and fourth-grade students and 32 college students were divided, within each age group, into four delay groups: 0-hour, 4-hour, 1-day, and 7-day. In the second experiment, conducted to clarify a question of visual presentation arising in the first experiment, 16 college students were divided into two delay groups, 0-hour and 1-day. In the first experiment, subjects were presented with a continuous series of 200 nouns, half seen and half heard, and asked to judge whether each word was "new" or "old," and if "old," whether it had previously appeared in the same or a different modality. A second test was administered after the appropriate delay for the group. The second experiment was conducted similarly, with a change in the visual presentation and with only two delay groups. Results show that the forgetting rates for effortfully encoded information (word identification) and for automatically encoded information (presentation modality) do not vary from middle childhood to early adulthood. However, modality identification declines gradually with time, while word identification remains high initially and declines rapidly later. Information about input modes lasted at least 4 hours in both children and adults, with some remaining in memory for 7 days. (MSE)