The Silver Brumby books are brilliant if you can get hold of them, really well written and as they are about wild horses I would think probably suitable for both girls and boys but children aren't my strong point so don't take my word for it!
There are quite a few horsey computer games out there too - I don't know if there are any that are educational but possibly worth considering for children that aren't too keen on reading - some of them are quite expensive but others are available for the same price as a good hardback book.
The Saddle Club books are probably still easy to get hold of but I would definitely say more for girls, I don't know what reading age they are suitable for, I just read anything I could get my hands on when I was younger....and now I'm reading all my kids animal stories again

Joyce Stranger has written some brilliant animal stories, some horsey and some not, she writes from her own experience and has a common sense approach to animals, again I'm not sure of reading age, I think she's done a few for younger children,
The Secret of Hunter's Keep is aimed more at younger readers I would say and the main character is a boy, it's got secret passageways and unexpected discoveries as well as the sort of writing about animals (dogs and wild animals rather than horses in this case) where you learn as you're reading it without even realising. I rediscovered Joyce Stranger's book when I found a couple in a National Trust second hand book shop and then made the mistake of looking on eBay/Amazon to see what else she'd written, turns out she wrote quite a bit

I'm on my 3rd...or maybe 4th reading of The Stallion now

If you want any more info on any of the books I've mentioned feel free to pm me but I will warn you I have a degree in English Lit so you may get an essay for a reply

Have you thought about horse DVDs? I think there is a series called The Stables which is aimed at kids that you can buy in Robinsons where I
did not spend over £100 on mostly DVDs and the latest Pippa Funnel PC game

It might be funny if I actually had a job to pay for all this!
