Way back when...
Ok, I can answer only to the extent that I witnessed. As a volunteer, I didn't see the behind-the-scenes workings that my madricha did (I had a madricha, female, and our gadna was lead by a different person- a mifakedet... also female). I know that one of the things she used to get very excited about was when we'd bring her construction paper. Apparently the army didn't give her many supplies! Anyways, each weekend (we had 3, I think) she would put together a 'weekend packet' for us, with maps, bus route information, suggestions on activities to do, specs on when we had to be back, phone numbers, etc. I'd suppose you could use the same weekend packets for each group you do. At the end of the program, she made a 'year book' kind of keeper- personalized to the group. I still have mine, love to look at it and remember the trip. She would help us find a job that was appropriate for us on the base. For example, I kept asking to do heavier work- they originally had me unpacking medical kits as they were returned from exercises, and I was bored out of my mind. She arranged for me to work with a group of guys with a high-power air gun spraying rust off old shelves, and then painting them. (I took a lot of pride in the base commander telling me he'd never seen a girl doing that kind of work before.) However, the 60-year old grandmother needed to do something in an less physical environment, so the madricha had her testing batteries in an air-conditioned office. The madricha was also the primary means of communication, as many of the other soldiers' English wasn't so good. (For example, I didn't know how to say 'heavy work' or 'I'm bored' in Hebrew and they didn't understand the English. I kept asking for 'avodah shel ish'- a man's work... it gave the soldiers a lot of laughs at my expense.) I believe the madricha coordinates the evening educational sessions, but she didn't actually present them. She may have been in charge of lining up Speaker A for Monday, Speaker B for Wednesday, and a tiyul for Tuesday, etc... We went to Tveria ('cause we were in the north) one evening, and also for our last night there, so I'm pretty sure that was organized by our madricha. We got her so drunk the last night, we had to call taxis to get her back to the base!! So fun. I digress. Everyone I've even known to go on Sar-El has gone with a very tzioni attitude, a hands-on approach, and yes, the atmosphere is one of work, not play. Don't get me wrong, we played and had a good time, too- but we worked. It's jobnik crap work, but it's still stuff that needs to be done, and we did it with pleasure. The madricha had to deal with some whining (no 60-year old grandmother wants to bunk with a bunch of teen girls while her husband is in a separate room with the boys), but there is a screening process in the States (or whatever country the trip is from. The language in the application is very clear- I remember it said that we'd be housed on army bases in the same fashion in which soldiers live. This means that sometimes, water dripping from a pipe overhead constitutes a shower. It was clear this was not Katamon, and we would not be coddled. At least, it was clear to me. The schedule was the same as the base, and I'm sure it varies from base to base. We had wake up at something like, 5:30 am, flag raising 15 minutes later, then work for 1-2 hours, then breakfast with the soldiers. Then work until lunch, work again until base closing. We (the volunteers) had dinner pretty much alone, because Netzafim was at the time a 'commuter base', and only a shell staff was there in the PM. The based closed about 1 1/2 hours before we had dinner. After dinner we would usually have hours of free time on the base, we could go to Tveria, and some nights there were the education sessions. I did the gadna option, and so we had to be up earlier to do morning exercises, and every night the gadna group had training sessions and exercises. Near the end, we went to the shooting range one evening. Sorry this is so long, but like I said, it was one of the best experiences I ever had. When I arrived, I literally didn't sleep for three days. I was so energized that I stayed up talking with the night shomer, going on rounds, all of it. I learned more Hebrew that month than in 10 years of Sunday school- I knew the word 'machzan' before I knew the word 'kelev'. really. I'd do the program again in an instant!