Throughout my Operating Systems course at Purdue, I had the opportunity to learn about and implement various system designs with the help of the stripped down Xinu OS. Due to Xinu's straight-forward and simple implementation, it becomes much easier to tinker with the moving parts that make up an OS one by one and learn how they really work.
Some of the projects I worked on:
To learn more about XINU, visit https://xinu.cs.purdue.edu/and https://github.com/xinu-os/xinu