We decided to visit Hanauma Bay while we had family visiting a few months ago. Everything, from the drive there, to the beautiful view looking down on the bay to the fish and coral you view while snorkeling, was just breathtaking!!
I highly recommend and underwater camera!
Look even the little ones can do it!! Here's my 4 year old snorkeling. He had a blast!!
It is quite a walk down to the bay and back up but well worth it!! If you have alot of stuff - or are just feeling lazy - they do offer a shuttle for a small fee!
As always don't forget to bring sunscreen and plenty of water!