And when not snorkeling don't place your mask on the top of your head like people do with sunglasses. Its incorrect to do so and will stretch out your mask.

I've taken my grand children snorkeling when they were 6 and 7. As for a 5 year old I've seen children that age do it but make sure the are under adult supervision at all times.

Get the inflatable vest like I recommended earlier. They come in sizes for adults and children and are specially designed for use when snorkeling. Regular life vests and personal personal floation device are designed to keep your head and upper torso out of the water making it more difficult to snorkel. When deflated a snorkel vest takes less room than a folded t-shirt.

Thanks Sunnyboy- I will have to go and visit my local dive shop and take a look at the gear. Do you think that a sporting goods store will carry it or should I look into a pool store- not sure if my town has a dive shop

I'd try a dive shop first (check your yellow pages - you'd be surprised how many small towns have dive shops). After that, try a sporting goods store that has diving equipment. I've never seen snorkel vests in a pool supply store but then again I don't know what is available in your town. If all that fails you can always do a "google" search and purchase one on line.