I wrote a news about the eBook "Networking with the Micro:bit" yesterday.
Today, there is eBook for fans of Raspberry Pi. A lot of info you can use for another SBC's like Orange Pi, Banana Pi or Nano Pi.

You can download the eBook here: https://www.raspberrypi.org/magpi-issues/Beginners_Book_v1.pdf

The second eBook is Raspberry Pi Annual 2018. You find how to use Scratch and RaspberryPi and also using of python in this book.

Download here: https://www.raspberrypi.org/magpi-issues/Annual2018.pdf