Twelve seventh grade and 23 eleventh grade students participated in a study that investigated age differences in the use of discourse planning. Subjects were given a list of games and asked to indicate which they knew well enough to explain to a peer. Subjects acting as speakers were seated at a table with a tape recorder present. Half had a listener present; half did not. Half had three minutes of planning time; half had no time at all to plan. Each subject was instructed to explain the game so that the listener (real or imagined) could then play it. Results indicated that both the amount and the level of planning increased with grade level. However, even at the higher grade level, some subjects did not plan, and most who did tried to write out their game descriptions. Overall, the findings suggest that some adolescents are unaware of the potential value of planning time and of ways in which to use it effectively when available. (FL)