What can you say with the footage you have? In most documentaries you could tell several stories. Take 5-10 minutes to write about the multiple threads of material you have and what you can say with it.
The construction of the school: Progress over multiple trips, effort that has been culminating over the last couple years.
Meaning of the school: Personal connection. Volunteers, students, workers, everyone has a different perspective.
People involved in the project. Same idea as above. Focus on an individual or small group maybe.
Actual opening day: why it's important. Speeches, dances, volunteers and students interacting.
Structure: How will you create structure in the piece? How will you connect different themes?
Find dialogue that builds over the course of the film
B-roll that connects a couple different ideas
Evolution: Look back at your Production and Pre-production journals. How have your ideas evolved since the beginning of the project
More clear idea of what I want to do after reviewing footage
Want to do something more personal instead of objective commentary on how the school was built
Make a shot log or a list of the footage you have that notes what is usable and what is not usable