There have been at least two recos for Pratchett and/or Discworld, and I have to third it. I read my first Pratchett around the same time I was reading HhGtG, just barely in high school, and didn’t know about the rest of his work. Years later I got into it and devoured all forty three or however many books.

I’d suggest Pratchett. Perhaps the witches series - or the Death series.

And in a slightly similar vein, T. Kingfisher’s Nettle and Bone.

What should I read next is a good resource for this. Personally I would suggest Pratchett. You can jump in anywhere with his books.

Books by Tamora Pierce would fit into her other book interest perfectly. All her Tortall books feature a strong heroine.

Maybe a bit left field, but I’d suggest something by the Brontë sisters (Wuthering Heights, Jane Eyre) or Jane Austen. Never too early to start on the classics and those should be reasonably approachable.

I really enjoyed the Artemis Fowl books at that age

Edit: Also, assuming the anti-religion aspect isn’t a deal breaker The Golden Compass/His Dark Materials series is a great read

A Connecticut Yankee in King Arthur’s Court, definitely age appropriate, and in a similar thematic range.

Douglas Adams’ Dirk Gently books.

I absolutely ate up Nancy Drew/Hardy Boys books when I was that age. And there’s about a zillion of them. Bookmobile FTW.

@snaptastic

As plenty of others have said, Terry Pratchett for sure. The Tiffany Aching books were written for younger readers but are not at all “childish”. You could start anywhere but I would suggest The Wee Free Men first.

Blood Meridian is a pretty good one if she likes adventures and historical drama with a teen protagonist

A few I really like:

Dune (sci-fi book about empires, space, politics, with magical elements)

Foundation (sci-fi series about rebuilding humanity from a collapsing galactic empire

The Golden Compass (Fantasy series with a female protagonist. Really excellent, but hard to summarize without spoilers)

There is an absolutely fantastic series called The Gilded Ones by Namina Forna that she would probably love; I saw it on a list of books that are a way better alternative to Harry Potter, read it, and haven’t stopped recommending it to others.

The Wayfarers series by Becky Chambers is a great warm-and-cozy kind of sci-fi, also well worth the read.

The House In The Cerulean Sea by T. J. Klune is a beautiful read about a group home of misfit children

The Deep by Rivers Solomon, an interesting twist on a mermaid story

The Psychology of Time Travel by Kate Mascarenhas is a really cool story that mixes up a murder mystery with time traveling

The Maise Dobbs series by Jacqueline Winspear; the series starts in the 1910s and follows a young girl who grows up to become a private investigator in the 20s and 30s

Almost anything by Neil Gaiman, but particularly The Graveyard and Coraline are awesome, creepy reads, if she’s looking for something like that

I loved Robin McKinley’s books at that age. She might like Jasper Fforde’s books.

Steelheart by Brandon Sanderson is good, probably on the more grisly side for a tween (probably in the same vein as Hunger Games?). Elantris (also by Sanderson) is a great read too.

My Side of the Mountain

The Cytoverse series by Brandon Sanderson, starting with Skyward. Age appropriate, female protagonist, sci-fi.

Also, I see someone else in this thread recommended Blood Meridian, and I feel like I should say that’s not a good recommendation for that age group. It’s a good book, and Cormac McCarthy is a great writer, don’t get me wrong, but it is also bleak, super violent, and dense.