A Hat Full of Sky is entertaining and fun read about a young witch in training in the classic fairy style.
In the first Tiffany Aching book she rescues her little brother from the Fairy Queen and becomes the kelda of the wee free men. The macfeagle are not exactly like brownies in that if you leave them milk they won't help you do your chores. If you leave them whiskey they'll try to help but it won't be the sort of help you'd want. She realises she's a witch despite all prior claims by witches that the Chalk lands don't breed good witches on account they are too soft. This book is about her continuing education as a witch.
Tiffany is sent to train with Miss Level who is not a twin but one person with two bodies. Miss Level's idea of witchcraft is helping the poor and elderly in her community which is a thankless task for a child unless your Pollyanna. Tiffany's own frustrations at being treated like a child come out when she's possessed by a Hiver. She reminded me a bit of Harry Potter in Order of the Phoenix since even after they've accomplished a huge feat they are still excluded from the adults.
The hiver has Tiffany's memories and somewhat of her personality except for the moral part that would've prevented her from taking advantage of others or saying the rudest things we might think about a trying person.
I loved the new stories we heard about her beloved Granny Aching. She was my favourite character in the Wee Free Men despite that she was dead.