I have been absent for a couple weeks so I am hesitant to enter the conversation, but I believe that you are sharing what the authors describe as first relying on personal and social motivation before extrinsic rewards. My sense is that there was one or more "opinion leader" on your team and that this was noticed by others in the school. The "reward" for this effort may be the changes to the writing curriculum that influenced work across the school. Those on your team experienced satisfaction and pride for contributing to work that others perceived as successful and supportive of them. People want to feel satisfaction and pride in their work, powerful motivators for where and when we choose to engage. The "reward" may also have been the feedback team members received from their colleagues for their efforts. Positive feedback and a sense of appreciation can also be powerful intrinsic motivators. Others will want to become part of these efforts for these reasons.
Maybe paying them a stipend or some other extrinsic reward would result in others wanting to join an effort such as you describe, but I don't think it would result in similar behavior or sustain over time.
