Here are a few resources:

1. USFIRST Grants page
2. Federal Grants (Grants.gov)
3. School Related Grants (If you're affiliated with a school district)
4. Grantsnet; check under the 'undergraduate' section for junior-high school and high-school opportunities.
5. Google

Most of the appliations for these sites are downloadable from their respective pages.

Hope this helps.