My friend Bob is a Navigator. I think they tell the Captain which way to steer the ship. At night they pull out their little telescope gizmo and look at a star and sing the Navigator Song
"Star light, star bright
First star I see tonight.
I wish I may,
I wish I might,
Find the way to Cozumel."
Then they pull out their Magic 8-Ball to find the answer.
During the day, they consult their "Charts". I think a chart is either a map or a listing of how well their song is doing.
"The Navigator Song is number 3 on the Rhythm and Blues charts."
The Navigator is the person the Captain sends into the gas station to get directions.
Oh, it's also a great daily newspaper on the ship. Other posters have given you the link. You might get a set of water-color markers for your trip (they don't "bleed" through paper). Give a different colored one to each person in the family so they can highlight the activities on the Navigator that they want to see.