We did our first trip with kids last year (8 & 10). Great time and going back next week.
Sleep aboard the night before. Let's everyone get settled somewhat and chance to teach/explain the boat without any pressure of also trying to do provisioning, boat check-out and get off the dock right away.
Short trip first day. We went to Cooper Island. . .only an hour away so everyone got used to being on the boat and easily snorkeling (it was very calm).
Conservative first snorkeling. Started okay but after a few minutes my son's mask became an issue. Straps needed to be adjusted. . .he was still close to the boat so after a little salt water in the eyes all was okay. Ten minutes later my daughter was having issues with her snorkel. We were further from the boat, but it was very calm so I was able to fix pretty easily. If we had gone off the dinghy or in rougher conditions, I think it would have been a bad first experience. By the second day they had everything figured out and were constantly in the water.
Flexible - both with the itinerary and daily schedule.
Dinners - Agree 100% with StormJib. All day in the sun makes for tired kids by dinner time. Except for the Leverick BBQ (recommended), we never had a set schedule for dinner. It usually ended up being some combination of a snack after anchoring, appetizers at happy hour and a little snack when back on the boat. . .depended on how everyone was feeling.
Night at the dock. We loved Leverick (others suggest Scrub). Nice to be able to get on/off the boat without the dinghy, do some provisioning, top off water, take a real shower, etc. We also rented a car and spent a day exploring Virgin Gorda (and the baths) which we really enjoyed. We found a little ice cream shop in Spanish Town (Yum Yums) which really hit the spot.
First Aid - Certain items are hard to find once away from Road Town. . .we wish we had children's advil and pepto, aloe, and itch cream last trip.
Down Time - Don't schedule too much every day. We discovered my 8 year old son was using some of the down time to sit at the salon table write several pages in a journal every day. What a great keepsake to have.
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