Usually, my husband and I will take turns going into the ocean. One of us will stay on the beach with our valuables (that will occasionally include a camera) while the other goes into the water with our son.
For those times we don't bring the camera, my husband carries our ship ID and photo ID in a zippered pocket in his swim trunks. We also never take our passport ashore, but have a photocopy of the first page. These are all put into a ziploc -- no problems as of yet.
On some beaches they have lockers you can rent to put your stuff in. We have waterproof pouches that go around our neck that we put our cruise card, money, and credit cards in. If we're not going on a sail/snorkel, I usually take my 35mm camera, which is old and not worth much. I put the camera in my water shoe, and try to cover them with my towel. You can also get a couple of disposable cameras. So far, we've not had any problems. Best wishes!
We have the water tight plastic "box" that is big enough for the credit cards, drivers license and cash. We got ours from the on board ship store and they have a rope attached to tie it onto you so you don't lose it.
You can go to scuba stores and get a similar deal. As for the cameras and other stuff, I wouldn't leave it sitting on the beach un-attended unless it would not upset you too much to lose it. For the beach we normally bring the disposable water proof cameras anyway...
I use the plastic box things too but they're not always water tight like they're supposed to be. Bring a zip lock baggie to put inside of it.
I live in Florida, I see them everywhere, drugstores, department stores in the beach wear isle. If you buy them on the ship, they're going to cost more, so look out for them in the stores before you leave. Even so I don't think they're that expensive on the ship really, maybe $5?? Wear the thing stuffed in your life jacket just in case to keep it from flying open accidentally. I've never had that happen, but you never know.
lbt43- Sorry I didn't see your question until now. But I think Scott responded well. The tie string is reliable, but aside from tying it to my bathing suit draw strings, my suit also has a pocket that velcors shut because you can never be too safe. I agree in that they never seem to be fully water proof, so the baggie idea is good. Or you can go to a scuba store and buy a water tight pouch. I don't know what the scuba version would cost, but the plastic box thing runs less than $5. I think we paid $6 on the ship,but as scott says, look at the beach isle in a local store and you can probably find them cheaper
We used the plastic box too. It's small, yet it holds a credit card, a photo copy of our passport, our sea passes and a few dollars. We made a photo copy of the 1st page of our passports to carry with us, we could fit the first page of our passport on one 8 x 11 piece of paper ( all three on one piece of paper).