Megan Hanson is the director of Root Down LA, a project of Community Partners that convinces youth in South LA to eat their veggies, educate their peers, and advocate for healthy food in urban areas. She doesn't use a form letter at all. Instead, here’s what has worked for her project’s efforts to inspire further giving through their thank-you materials:

“We personalize most of our thank-yous but we did send out a round of thank-you ‘packets’ to about 15-20 of our largest donors/closest supporters this fall that consisted of the following:

1. Simple cards made by our Youth Leaders that featured photos from our cooking, nutrition and new horticultural programs. The words 'Thank you!" appeared on every card along with a sentence about what the kids feel grateful we've been given, e.g. "Thank you for helping us bring healthier food to our school." "Thank you for helping us visit other healthy food organizations in our trip to San Francisco last summer." "Thank you for helping us plant a school garden."
2. One student taped some seeds to small seed stakes and drew the fruit or veggie that would grow from the seed. She got tired of making them so we put those in just some of our packets.
3. And then yes, a letter of thanks from the organization (click HERE to read the letter).
4. AND a handwritten note from me on a nice piece of stationery with a flower on it.

We drew one $5,000 donation and another $500 donation directly in response to these cards and we received feedback that people love and appreciate the photos. One donor even keeps hers hung above her desk. Sorry I didn’t keep sample copies to share!”