The phrase "powerful lever" refers to a tool or strategy that can greatly influence or achieve something important. It represents having a strong advantage or impactful means to accomplish a goal. Full definition
It also presents the most powerful lever for the exercise of leadership. (nsba.org)
And if that can be done correctly, traditional instruction delivered by the teachers already in classrooms may turn out to be the most powerful lever we have for improving school performance after all. (theatlantic.com)
I personally feel like curriculum is a very powerful lever for change. (educationnext.org)