Who is the author?

[Lynn]

How much of this book do you think her father wrote?

[Anirudh]

I guess the Pakistani political history and certain analogies (comparing the 2005 earthquake to Connecticut - impossible for a girl who didn't know where Birmingham was), mostly, it was the co-author, Christina Lamb who wrote it. The others I believe are Malala's own - edited by Lamb.

[Amit]

she must be the story teller, It was Lamb who actually wrote this book.. This girl was merely at her secondary classes...but the fact that she has already described that she had an interview in English when she was at 9th standard.., her ability for English language cannot be denied..

[Maddison]

According to goodreads it was co written

[Jane]

The Inscription says Malala Yousafzai with Christina Lamb. Likely it was co written.
If you watch Malala's interviews and speeches, she is quite an articulate well spoken young lady.