I am also in the same situation as you. Luckily, I got a book of Mark Cade (for the old version though) from my friend which has a sample assignment. After reading the assignment, I am thinking its important to work on this first, create a design and then validate it against the solution given by Cade in the book. For example, after reading the assignment I am getting so many doubts about various things.
I am looking to buy the book for the 5.0 version (not sure if one such thing is available).
I think preparing in such a way will correct our mistakes and also improve our confidence - this should help us in finishing the actual assignment faster - though this will take more time...
1.4, SCEA 5.0 Part I.