Just wanted to recommend the Warrior Cats books by Erin Hunter.

[Mumwhensdinnerready]

DS2 aged 11 is completely addicted to these books.
He's now bereft as he has just finished the last book of the first series.
However I've been on Amazon and the library website and find there are about 30 Warrior Cats books, over 4 or 5 series by this author , who is not in fact one person but three. They seem to be fantasy / adventure stories which follow the fortunes of tribes of cats. DS lent them to a friend at school and she loved them too.

ooh age range?

DS is an avid reader and these are well within his ability so I'd say age 10 to 13 depending on reading ability, and suitable for boy or girl.

My children are obsessed by these too. ds started (he is 10 and dyslexic, so we were very pleased when he got hooked). He's read the first three series, and a couple of stand alone books too. Then dd got into them (she's 8) and she is now into the second series.

They both play a lot of Warriors related games together too. they are all about cat clans, and apparently quite emotional too (a fair few times I have found them in tears about some cat that has just been killed/died).

There are also some books by the same Trio about polar bears (Seekers).

My dd aged 11 has just discovered these - she has never needed encouragement to read but these have taken it to another level!