Ask HN: Grants for personal development/engineering projects?

I was looking for a way to keep my kids' minds engaged this summer (instead of letting them watch TV for 30 hours per day), and decided that a family summer project would be a great way of having fun as well as learning some new things (for all of us). The project we decided on was to build a quadcopter drone. In planning this out, I decided I wanted to document the entire process, use a Raspberry Pi as the core, and do as much of the engineering and software development as I could. I realized that by using open source software, commodity hardware, open-sourcing all of the custom code that I write, and thoroughly documenting the entire process, I could provide a very educational guide for hobbyists to use at home, or even teachers to use in their classroms.

I mentioned this to a coworker, and he thought I should see if I could find a grant to help defray some of the costs associated with it. Does anyone know of any organizations that provide grants for personal projects such as this? The goal is to produce a completed product for under $250, but I fully recognize that there will be additional costs associated with building prototypes, buying the necessary tools, etc. Ideally, I'd like the total cost of all the research, development, and engineering to be less than $1500 total (sub-$1000 is my real goal). Since I want this to be useful in teaching children more about engineering and software development, it's important to me that the expenses are minimal for the finished product.

Can anyone give me any leads on individuals, foundations, companies, etc. that might provide grants to help defray some of these costs? I'd really appreciate any recommendations you can provide. And I'll be sure to post a link once we begin work so you can follow our progress!