Your goal is to do two things:
1) Come up with the reasoning behind a system, e.g. what is it's purpose. Document this.
2) Now go to any website vendor that allows wishlists and build your machine. Be sure and document the following in your lab:
3) Justify why you chose what you chose.
4) Provide the wishlist and the final pricing of the system.
5) Report any reviews or other issues you can find that you googled about that mobo/cpu/ram combination.