I went home last summer (after being in the US for a year and half) and the only documents I took with me were my I-20s, passport (with VISA sticker, of course) and I-94 card I got when I entered US for the first time. I also had my university ID and social security card with me but I don't remember using them. If you have them, take them with  you just in case.

Here's the process:
1. For I-20, go to international services office in your college/university and say that you're going home for a few months. They'll endorse your I-20 or give you new I-20 if you changed your major since you entered USA (that's what happened to me and I took both I-20s with me). If you haven't endorsed your I-20, do it the first thing tomorrow because it takes a few days.
2. your I-94 card is usually stitched to your passport, if not find it and take it with you. As far as I remember, the airlines staff took mine and shredded it. You'll get a new card at the port of entry when you come back and that's when you'll be showing your endorsed I-20 to the immigration officer to get a new I-94 card
You DON'T have to take all those documents you prepared for VISA application, I didn't. 

In summary, you'll need: an endorsed I-20, passport with unexpired visa stamp, I-94 card, college ID, and if you have - SSC and driver's licence.

That's all you need to worry regarding documents. If you have other questions, let me know.
Have fun!