How To Write A Letter Giving A Donation . “your donation of $25 will help provide a backpack full of school supplies for a local student in need.”. People like you are the reason we can continue supporting [your cause], and we truly can’t thank you enough. Sample Letter Asking For Donations For School business form letter from www.businessformlettertemplate.com Donation letters are those that nonprofit organizations, individuals, and charity groups request for donations or sponsorship.they are also used for solicitation and fundraising activities. This is your first opportunity to be recognizable, and thus, trustworthy. Here is a sample of the letter.