I have 4 kids ages 3, 6, 9, and 12 and we've never been snorkeling before. I'm wondering if the 3 and 6 year olds can do this. If not, how do we keep the younger ones entertained while the older kids, my husband , and I go snorkeling. Also, do we snorkel near the shore and can get in and out of the water as we need to, or we have to get on a boat to the snorkeling place? TIA for your advice!