We actually did this several months after a cruise for a week. We thought we would try to bring some of that DCL Magic into our everyday lives. Day 1 we made a fancy non- alcoholic Drink of the day, the first "sea day" we unplugged all our devices because we all know there isn't great internet at sea and had unlimited ice cream for the day. Other things we did included a late night movie with snacks, turn down service complete with some of the DCL chocolates we always come home with (we don't actually like them much.....), We had a "spa day" with our DCL shampoos and cucumber water. We went on a Port Adventure ( does not apply now, but you could plan a fun activity at home) and even had the cold wash clothes to cool off at ready in the fridge for when we "returned onboard". We did a workout while watching a Pixar movie. We watched some Rick Steves shows like we were on a tour to the port, we folded the toilet paper for like the cabin stewarts always do, we made a fancy breakfast and ate it "out on deck" (outside). We did burn some nice scented candles to give us that " on the ship feel" because every time you walk past certain area (Senses Spa, or the kids club when they do the strawberry something or other) you know where you are by the scent. We watched Newies the Broadway production/made into a movie theater event. We did a fun for all ages olive oil seminar, and then cooked dinner with it, and finished off our cruise with another drink of the day.
It ended up being a really fun week in our house (we still had to go to work/ life so it wasn't a full vacation). You could easily set up some trivia (Name that Disney Tune, pub trivia etc), add a craft time (veggie car race?) Disney themed board games, slime making. You could "check them into the kids club" except you are then the club host and do some of the activities they do ( you can do the trace in table at home with some work, also the painting cells, slime making, sloppy science, video game room, ice breakers etc). Hide Mickey silhouettes around the house and have a hidden Mickey contest one day. Turn on your favorite game show on tv/video and play along as a family like you would if you went to one of the game shows live on ship. Save all your recyclables for a week or so and then have the family split into teams and spend the week working on your floating ship to test in the bathtub! Maybe make up postcards to "send" each day from your journey (digital works too). Lay out on "deck" one day in your swim wear. Have a Sail away Party on day one. Do a Muster Drill.
Go through some old navigators and see what you could modify and do at home. If you have any questions as to how we did it, just ask. Happy to share.