The Boy Scouts of America have almost 50 million living alumni throughout the United States, so almost everyone knows about Eagle Scout projects. Therefore, finding grants for Eagle Scout projects is easier than for unknown individuals or organizations. The key to finding funding is to match the project with the appropriate donor. Nationally, the Boy Scout Organization partners with large organizations, including AT&T, Exxon-Mobil and Bass Pro Shops in multimillion dollar sponsorships but your Eagle Scout project does not need that level of sponsorship.
Eagle Scout projects do not cost millions of dollars, so you don't need to search for major government or corporate grants. Simply look locally to the community that will directly benefit from the project. In your Eagle Scout Workbook, it states that the donor must be made aware of who will benefit from the project and that it isn't the Boy Scouts! The key is to match the donor to the type of project. If it is a local waterway cleanup, try getting donations from a local boating or fishing-supply company. They will be more favorably inclined because it is something they are interested in and their business will benefit from being associated with the project.
If your Eagle Scout project involves construction materials (and many do), a good source of grants would be your local building supply house. There are both local and national chains that specialize in building materials. Large, nationwide building-supply companies donate thousands of dollars' worth of materials every year to support their local communities. One of the primary recipients is Habitat for Humanity, but because you will be using considerably fewer resources than an entire house, local Managers may be able to authorize a donation without a long application process. They may also donate slightly damaged materials that are still usable for smaller projects like yours.
The Eagle Scout Leadership Service Project Workbook only provides very general guidelines regarding the nature of the project and sources of funding. At first, this may be frustrating, but this is where your leadership comes into play. You have wide latitude to choose your project and find appropriate funding, which can be through fundraisers or through specific donations from individuals and companies. Although the project itself can't be a fundraiser, fundraising can be done in order to complete the project.
Many business owners are former Boy Scouts. Therefore, if you approach them with a worthwhile project, they are likely to be willing to donate a few hundred dollars. Do not expect small local businesses to fund thousands of dollars. It is best to try for several smaller grants rather than one large one. With an average grant of $200 to $400 from as few as five local businesses, you can raise $1,000 to $2,000, which should be enough for most Eagle Scout projects. Remember, according to the guidelines, you must return any unused money.