2 Paint the box.

Use tempera or poster paint to paint the inside of your box. Paint the walls light blue to make your diorama's background. You can paint details like clouds or falling snow.

Paint the ground white for a snowy landscape. You can include a body of water to show how integral the sea is to polar life.

You can also paint the outside of the box, if you like. Use acrylic paint if your box has a glossy finish.