Life at NSI.... from someone who's there.
First of all, congrats on being selected to STA-21. I'm an FY03 selectee, halfway through NSI. I attended 6-month BOOST first. We finally graduate and get out of here on April 23. I was selected with guaranteed NFO option, plan to graduate from college in May 2006.
Basically everything you've read so far is true - our typical week runs like this:
Reveille at 0500 (even though we don't always do anything right away)
PT M-W-F at 0640 (running the trail, approx. 3.4 miles, with calisthenics after) DO NOT FAIL THE PFA or be out of body fat standards. You may be packing your bags.
Classes in Weapons, Engineering, and Seapower on M-W-F from 0830-1520.
Classes in Nav I and II on T/Th at the same time. (Yes, that's 6 classes each day!)
Intro to Naval Science lectures once a week; "distance learning" format where you take one final and that's your grade in the course.
There's also "mentoring" with an assigned officer, it's not very beneficial since most of them are SWOs and don't know much about the other communities.
School is DEATH BY POWERPOINT. No joke!!!! You can print out the slides and still get all the information you need, with the books as a reference.
It really is similar to boot camp, except with liberty and no open-bay barracks. Community heads, though. The rush after PT is unreal, especially since most days we're lucky to have 30 minutes to get ready before class.
Inspections (room/locker/uniform) once a week (different uniform every time, of course), every other week for a "pennant" you have on your company guidon. So far, only one company has any guidons - all of them. Haha.
We wore PT gear for the first few days (a week and a half for the new guys, 3 days for the prior BOOSTers - they had a week of indoc while we had final exams) then winter blues and CNT khakis every Friday.
Liberty is pretty strict; none during the week until Week 3, but F-Su we get it until 2200. This begins Week 5 for us, so I think we get Cinderella liberty on the weekend. We also now have liberty M-Th from 1700-2200. No civilian clothes, OC blues is the liberty uniform (no khakis). Civilian clothes during Week 8, from what I hear. (Week 9 is the last week.) We wear PT gear if we're not in uniform in the barracks. "Regular" pajamas are only authorized to and from the head if you're in the rack.
We live in 2-man rooms, minimal decorating allowed (as in 2 photos and a clock radio). There are 2 TVs for community use, vending machines, laundry, etc. but you won't want to bring a lot of stuff - you'll have to store most of it. You can bring your own blanket/sleeping bag but you have to lock it up during the day. The rooms have to be inspection ready at all times. It's 2 bunkbeds (top is rack, bottom is desk), 2 nightstands, 2 lockers. 10'x14'.
If you plan to go off base often for liberty, you may want a car unless you can make friends and get rides everywhere. Some people never go anywhere, but if you want to get away (as I often do), you'll want a car. Like the other post said - if you're on the West Coast, it may not be worth it to drive all the way out here for just 9 weeks. Newport is a nice town; being here in the spring and summer should be nice for you. There are tons of bars and clubs downtown and lots of other things within a short drive (like Boston).
I hope that helps - let me know if you have any questions!!!!
This might help too -
https://www.sta-21.navy.mil/nsiwelcome_10_03.doc
https://www.cnet.navy.mil/netc/boost/nsipage.htm