Creative mamas PLEASE HELP!! LOOK WHAT I DID!!

For the castle you can paint green hills and flowers.  Paing a blue sky with clouds.  Maybe for the boat do waves and fish and stuff?  A dolphin jumping out would look pretty cool, some sort of animal.

how about the scene of a castle courtyard with a garden and beautiful maidens (princesses) for your daughter's room and an oceanbeach with wild animals in the distance kind of like an africa coastline maybe   i hope this helps it's just what the beds made me think of

You could do castle guards, flags, horses, etc around dd's two walls, and then for the remaining two, make it look like ds's bed is in the moat of the castle....have croc's and frogs, guards, cannon's, etc.

What size beds are they?  If they were toddler size beds, I would consider waiting until you figure out what other beds/themes you are going to get them.  Your four-year-old will likely be outgrowing that boat soon.

I was thinking something similar but how do I make the water and land conect?? maybe a lake.. 

Quoting Tysonsmom111006:

For the castle you can paint green hills and flowers.  Paing a blue sky with clouds.  Maybe for the boat do waves and fish and stuff?  A dolphin jumping out would look pretty cool, some sort of animal.

THATS A REALLY COOL IDEA.. 

Quoting Blondee512:

You could do castle guards, flags, horses, etc around dd's two walls, and then for the remaining two, make it look like ds's bed is in the moat of the castle....have croc's and frogs, guards, cannon's, etc.

You should check out ratmyspace.com. People have put some amazing murals up there. I have to ask, where did you get the beds? They're so cute! I esp love the boat.

Get some coloring books and/or simply illustrated children's books about princesses and boating.  Look for simple line drawings.  When you find an illustration that you and your kids like, trace it onto an overhead sheet, borrow an overhead from a school for the weekend, project it onto the wall, and trace it.  Do whatever your kids like.  The tracing idea makes it so you don't have to eliminate ideas because you don't think you can draw it yourself.  If your daughter likes My Little Pony, you can have princess ponies on the wall with rainbows and all sorts of things.  You can find all sorts of fish illustrations for your son's room, if he likes Sponge Bob, maybe his pineapple under the sea can move into your son's room.  Ask your kids what they want on their walls, and go find pictures to trace.  Have fun! 

They are toddler beds bUt I don't mind repainting in a year or so ... I love doing stuff like this..

Quoting Melissa0216:

What size beds are they?  If they were toddler size beds, I would consider waiting until you figure out what other beds/themes you are going to get them.  Your four-year-old will likely be outgrowing that boat soon.

If they share a room you can make your DD's walls look like a princess island, which would easily incorporate the ocean/water theme of your son's bed. dolphins, whales, fish, under water plants for the water, and bright grass, trees, flowers, ect for your DD.  Hope this helped.