Thank you for submitting your questions to ask an advisor. It sounds to me that you are asking about the most effective way to implement your program, correct? If so, there are many components to doing program implementation. I would recommend browsing through the chapters on "Implementing Promising Community Interventions" in the community toolbox: https://ctb.ku.edu/en/table-of-contents. These are chapters 20-26.
It also sounds like you are interested in aspects of community buy-in as you noted, "We want to encourage them [educators] to use earth boxes or grow boxes in their classrooms to grow food. You may also be interested in reading chapters 6 and 7 in the same link above.
To summarize my thoughts on a couple of these approaches, I think it may be first most beneficial to assess educators' interest in adopting the program. I would recommend starting by understanding who you want to approach to include the boxes in their classrooms. You may even want to make a list of these educators. I would then contact each of them and ask them to meet with you one-on-one to assess their potential interest in adopting the boxes in their classrooms. You may also think about the supports your program brings to assist with the implementation. If you leave it solely up to educators (especially if they don't have complete interest), they may not as easily adopt the program as if your team has supports.
If there are some aspects I am missing with your program, which I am assuming I am, please feel free to clarify.
Good luck! I hope my response is helpful.