Learning game developement requires a lot more than just an explaination of the syntax, anyone can pick up the syntax. What you really should be learning/teaching is what is going on when each of the functions is used, and how the back buffer works, how they swap from front to back. There are 3 great books that have been suggested to me by a few friends in the business (Big Huge Games), and they are: The Geometry Toolbox, Essential Mathematics for 3D Games and Interactive Applications, and I can't remember the last book but the above two are already a lot of reading.
However, just for future reference, it never really is important to learn the Win32 API since you really dont use it very much in Game developement. But it is a good skill to pick up on.