Discuss hypotheses individually with each group. Modify if project impractical, without taking over. Teams gather data. Based on evaluations of the presentations by the facilitator - consensus was that all goals of the project were met. For my introductory class, I go into the field with my class, wander around, explore and answer general questions.
General exploration includes an introduction to the habitat and natural history.
Then we go back to the lab and develop research questions. This approach utilizes the collective group knowledge. Students need background knowledge. This makes a difference in sophisticated versus naive wandering. Each week in lab my students develop questions at the end of lab.