Three characters on the .org, X-for-Y. K4O reads as knowledge for others, kits for orphans, or kids for outdoors.
Kids for outdoors, or outdoor education more broadly, is a real and growing area. Nature deficit, school outdoor programmes, and youth conservation work all attract funding, and the organisations running them are local nonprofits with exactly the naming problem a short domain solves.
Knowledge for others suits open education and knowledge-sharing initiatives.
The 4-as-for convention is standard in this sector for a practical reason: it produces names that fit on a T-shirt, a minibus, a banner, and a funding application, and that survive being said once at a community meeting. Three characters is the shortest form of that.
Fixed supply, matching extension, established convention.
The name is available. Enquiries welcome.