Use scissors to cut newspaper or craft paper into strips measuring 2 inches wide by 5 inches long. Cut about 50 or 60 strips.
Put one part water to two parts flour in a pot. You can replicate the mixture amount as needed during this project.
Heat the mixture on the stove until it just begins to bubble, then remove it. Let it cool.
Inflate a large round balloon. Knot the end.
Dip the paper strips into the paper mache mixture one at a time, wiping off the excess gently.
Drape the strips onto the balloon, one at a time. Smooth out any air bubbles with your fingers.
Cover the balloon with the paper mache strips until you have covered it in four to five layers.
Stretch a piece of twine across a space, such as a doorway or hallway, and anchor it at either end. Make sure the twine is taut.
Clip the knot of the balloon onto the twine using a paper clamp.
Allow the balloon to remain clamped to the twine until it dries completely, which can take a few hours. The paper mache should be hard once it is dry.
Pop the balloon with a straight pin. The paper mache will remain in tact, but the balloon will be deflated inside. Remove the balloon.
Paint the entire outside of the balloon blue.
Paint the landforms of the Earth green or brown to represent continents and islands.
Allow the paint to dry completely.