I've worked 3 weeks for Sprout, an NGO located in Manhattan, New York City who organizes vacations and one-day-trips for people with disabilities. After a two-day training we were off on trips with the participants. normally you are three leaders with a group of 11 clients and a vacation-trip normally takes four to six days. Working with these people is demanding and tiring, as you are on 24h duty, but it is also lots of fun and very rewarding!
On the first day of the trip you meet the participants, get to know them (try to remember all the names..), sort out their luggage, pack the van and then off you go. The several hours ride is a good opportunity to talk to clients, get to know them better and feel the group's vibe. Once you arrived at your destination it's late afternoon and you're probably tired (and so are the clients) so you have a rest in the previously booked hotel and find a restaurant to have dinner at. And that's it for the first day. The next days you plan some activities, like going to the cinema, riding a boat, going to a fun-park, whatever the place has to offer and whatever the participants like and are able to do. Of course you also have to help them with their ADLs (daily activities we perform for self-care such as feeding ourselves, bathing, dressing, grooming) and that's about it. If it is the first time you're volunteering for Sprout you won't be bothered with medication because that's the more experienced leader's job.
So, if you're an easy-going and open-minded person, go for it! I had the time of my life, it was really so much fun! The people who work there are super nice and caring and they would never force you to do anything you don't feel comfortable with.
Also when you're off work you stay in one of the best hostels I've ever seen situated in the upper-west-side of Manhattan!
Only one thing: Be prepared to eat lots of heavy food, cause that's what clients love! ;)