ABSTRACTField trips can provide unique opportunities for authentic, meaningful, and self‐determined learning. Capitalizing on these opportunities requires that field trips be structured. A common way to do this is through the use of educational materials such as worksheets. The extent to which the guide's or teacher's autonomy‐supportive or controlling motivating style influences learning structured by worksheets has not yet been investigated. We conducted two studies focusing on this specific issue. We hypothesized that autonomy‐support is beneficial to intrinsic motivation and cognitive achievement. The setting for our research involved a field trip to the local zoo. The participants were 100 fifth graders (medium achievers) for Study 1 and 106 fifth and sixth graders (high achievers) for Study 2. The classes were divided into two groups for each study. While completing worksheets, some classes were given autonomy‐supportive guidance and the others controlling guidance. We assessed the pupils’ intrinsic motivation and knowledge using a pre‐, post‐, follow‐up test design. Our research found that autonomy‐support appears to be beneficial to motivation and does not seem to impair cognitive achievement. The beneficial effect of autonomy‐support was found to be higher for the high‐achieving pupils than for the medium achievers.