Phil,
The more grassroots you make it, the better, more sustainable it will be. Mandated times and contracts are more impediments to participation. Seek out those teachers enthusiastic about participation, be flexible with scheduling. It will take time, but through word of mouth and seeing kids out there (and kids talking with kids), you will build a core group of participants. I have managed to fend off administrations that wanted contracts and assigned boxes and cleanest planter box contests, and over time (3 school years). We have an open learning community garden, where classes come (mostly every other week on an A/B rotation) and plant, cultivate, and harvest according to the season(with appropriate lessons sprinkled in). No assigned boxes. No contracts. Best Wishes.
Peace.
Fidel
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Fidel Garcia
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