Welcome to the DIS!!
12 yr old "That was awesome!"
9 yr old "It was great!"
6 yr old "I didn't like that!"
My DD, 6, panicked a little. She has used a mask in our pool but not used a snorkel. She got a little confused when she used the snorkel and sucked in some water.
I think that your family will love it. If you've never snorkeled before it's really great.