[saagarjha]

Though implementations differ, for any nontrivial task the problem of scheduling and resource allocation is a recurring theme and an important part of what an OS class “teaches”. But for many undergraduates an OS is also their first large project, perhaps one written in C. Really, there’s no “one” skill that a toy OS can offer, but anything in the area will give you a greater appreciation for how OSes in general might work and the problems they need to solve.