If you're part of the tribe that is more than willing to contribute their bit to the society, but don't know where to start from, keep Donate An Hour on your speed-dial. They assist in mentoring and teaching children from the underprivileged background, and all they ask from you is your time and some do-good attitude.
Do Your Bit: Donate An Hour And Spend Quality Time With Kids At This Social Startup
What Makes It Awesome
You'll be signing up to teach as well as spend some quality time with kids, in order to nudge them towards a brighter future. You can volunteer with them on a weekly basis, depending on your personal schedule. But whatever time you put into it, it's a given that you'll walk-out with a proud feeling of having helped someone in eventually leading a better life.
Also, for those who hesitate in giving monetary aid, the peeps here have only requested time (and nothing else) from you.
What Could Be Better
They have multiple centers in Gurgaon, but none in Delhi. So, you'll have to make the trip (totally worth it).