I volunteered for 2 weeks at the Street Children Education Project in Jaipur, India, with Sankalp. It was a wonderful experience and definitely too short. (I would recommend at least 3-4 weeks if you can do that, not only for the benefit of a stable/continuous presence for the children you'll be working with, but also for a chance to spend time with the other volunteers and really get to know the great city and its surroundings).
The children at the Street Kids education project were beautiful, mischievious, bright, eager, and all the other regular "kid" ingredients you might expect from kids all over the world! I had a class of 9 kids and although you only do 3 hours per day (mornings from 9-30 to 1) it was exhausting and tiring but very worthwhile. The little progress I was able to make with them over the 2 weeks was really rewarding :) I only wish I could have stayed longer. I think the fact that volunteers come and go so frequently, and there's no curriculum they follow (except for the older class, which I didn't have) makes it difficult for a sustained learning progression for the kids --- so a handover between volunteers is really necessary and worthwhile. If you do this project you will surely love it; today was my last day and it was really, really difficult to leave.
The volunteer house is in a safe area and you can easily get downtown in about 30 minutes with a cheap tuk-tuk ride. When I was there, there were about 10 or 11 other volunteers. Rooms have two bunk-beds each, so 4 to a room. There is a communal dining space, as well as an upstairs TV lounge, and a great terrace. The house is basic and you may have fewer luxuries than you're used to but it is very comfortable and safe and best of all the atmosphere is a great one with a range of people (aged 19 to 67 when I was there!) from all over the world. It is sort of like living in a university residence again in that you need to do your dishes and keep the common areas tidy as you are sharing them with everyone - and everyone has different standards of cleanliness etc. But the group dynamic worked really well and we all lived together no problems during the weeks I was there.
The cook and house manager, Punima, is fantastic and makes really great veg meals, as well as being extremely friendly and chatty! I will miss her happy voice, big smile, loads of questions, and great meals. Amita and Pranay, who run the organisation (and whose office is on the same floor of the house where Punima cooks/sleeps) are very helpful and kind and I wish them the very best of luck with this endeavour.