I am finding that the business of landscaping the CBD is amazingly complex, what with the various constituencies involved. Trees should be less controversial though.
I think the Olmsted Society would/could be that conservancy, and already takes donations for plantings. The business of moving the 20 year old trees they donated to make way for the Village Center is likely a sore point.
I believe the village government's planting fund has only $200 in it presently. There is a way to make a restricted gift I believe, although how restricted I don't know. Katie Rush could say.
I think the way you are going through the school is a good one, spatny. I think also that you will hear that planting that many trees at a time though would be a strain on Forestry's ability to maintain (high maintenance when they are young.)