This is a super informative book about arduino that also includes some tutorials. I believe this will be a great resource as it goes more in-depth about hardware and electrical engineering principles.

The Tab Book of Arduino Projects: 36 Things to Make with Shields and Proto Shields, Product details Publisher ‏ : ‎ McGraw-Hill Education Tab; 1st edition (October 2, 2014) Language ...

Educeeno is an arduino-based learning tool complete with tutorial book, designed for providing an easy path to learn more about electronics, and programming micro-controllers.