My favourite kernel development tutorial is bkerndev [0]. It provides easy-to-read sources that can be used as a good base for simple projects.
Shameless plug: I used bkerndev verbatim for my bare metal project - Nope OS [1] - a C64-like system that I built for my son when he was born, so that he could get to know computers the same way I did. :)
Shameless plug: I used bkerndev verbatim for my bare metal project - Nope OS [1] - a C64-like system that I built for my son when he was born, so that he could get to know computers the same way I did. :)
[0] http://www.osdever.net/bkerndev/Docs/intro.htm
[1] https://github.com/d99kris/nopeos