Time now to record the behavior. Also a space for your notes regarding antecedent and consequence information. That is the question. You the teacher are most likely the one who conducted the direct observation, collected the data, and logged the information. Unless there are monumental egos involved, you as the homeroom teacher will carry the most weight.
Public schools are busy places with never enough time to get most jobs done thoroughly.
Paper compliance is the honest name of the game. Make it look good and all will be fine. A major task confronting you, therefore, will be to ensure that the write-up is comprehensive and reflects the information you have collected. With sufficient data, patterns will emerge. Given the information the team has agreed on, the BO will state the functional behavior, the conditions, and the criterion.