The logo will need to be easily transferable and recognizable-to those experienced designers this probably goes without saying-but it will be on business cards, pamphlets, brochures, shirts, hats, etc. and will be the cornerstone of the newly developing website. It can be an amalgamation of horse and wheelchair, horse and crutches, etc, but it certainly doesn’t have to be that (and if it does please, please, make it creative). I don't want the kids or riders who will be wearing this to associate it specifically with a 'disability club'. The idea is that this transcends their disability.
Logos I like are the Firefox family of logos, New Belgium Brewery logos
A website I'll be hopefully modeling mine after is http://www.sheacenter.org
Please no clip art, etc. (Again I know this goes without saying for the experienced designers). This has to look professional and clean.
The tag line that accompanies the logo is "overcoming obstacles, one hoof at a time".
Good luck and I look forward to seeing your designs.