Although studying Earth's weather without expensive meteorology instruments is difficult, students can simulate their own weather conditions in science class. Add three drops of blue food coloring to 1 cup of water and stir. Pour the blue water into a 20-ounce clear plastic bottle and tilt the bottle at a 45-degree angle. Slowly pour 1 cup of cooking oil into the bottle and observe its movement. Teachers should discuss the properties of air masses with the class to explain why oil moves across the top of the water when added to the bottle.
The meeting of warm and cold fronts is effectively demonstrated in an experiment using inexpensive household items. Pour warm tap water in a baby food jar until it reaches the brim and stir in five drops of red food coloring. Fill a second jar of identical size with an equal amount of cold tap water and stir in five drops of blue food coloring. Cover the warm water jar with an index card and hold it tightly while inverting the jar. Place the warm jar directly over the cold jar. Hold both jars firmly with one hand while slowly removing the index card separating the two bodies of water. Once it is removed, gently turn the jars on their side, maintaining a firm seal by holding them tightly together, and observe how the two fronts travel in relation to each other.
Advanced science students will find the subject of weather fronts an excellent topic for a unique experiment. Build a 16-inch square box without a lid, using a whiteboard for the base and plexiglass for the walls. Center the box on a turntable and fill with water to a depth of 6 inches. Remove both ends of a coffee bean can and rub petroleum jelly around the lower rim. Place the can in the water so it extends above the water surface by a few inches. Create saline by mixing salt with water to the point of saturation and add red food coloring. Set the turntable to rotate at 15 rpm for 10 minutes and slowly replace the water in the coffee can with the colored saline.
Kindergarten teachers who want to explain air mass movement to young children find a simple experiment helpful and entertaining. Add blue food coloring to water and pour into an ice tray. Place in the freezer to set. Fill a plastic container two-thirds full with lukewarm water and let stand for one minute. Place a blue ice cube at one end of the container and add three drops of red food coloring the the other end of the container. Ask students to watch what happens and draw a picture. Discuss convection and the difference between warm and cold fronts of air.