I used to play only briefly, when my daughter wants to play on the same map together. We still play, but I've put a few poker hours into it now since finding the hardcore mode and the ocean maps. ;)
We limit our 9yr old to 3 hours of computer/tv time a day. They must have their school work done before this. They can choose what they want, within the limitations we have set for them.
3 hours is a lot, but parents are different. Some do even without screens. We have some days off screen a week, and let the kids play about 1 hour, less than watching movies, mostly in English an French.
I think I have seen my son diving into the ocean. Have a good time with your kids.
We home-school, so there's a LOT of extra time in the day. ;)
It's an interesting game in hardcore. In game, you can jump from any height and one square of water will stop you safely. When you've spent an hour or so on a map and do this, I get an adrenaline jump as I'm stepping off. If you miscalculate, you'll miss the square and the map is over. lol