The Pacific Gas and Electric website outlines an advanced experiment "Making Methane," that would serve well as a science project. One of the gases that makes up natural gas is methane. You can make this gas from decomposing organic material. This creates similar conditions to those that occurred when natural gas formed underneath the ground millions of years ago. This fast-forward process mimics the creation of natural gas, but, instead creates biogas, which is a mixture of carbon dioxide and methane. This is a 10-day experiment where you set up several samples of decomposable material in bottles with balloons over them. Place each sample in different environmental conditions to find out which conditions are most suitable for creating the biogas.
A basic natural gas experiment for a science project on "Rocks that Trap Gas" is also on the Pacific Gas and Electric website. In this experiment, you compare what happens to water when it is poured into a jar of sand and a jar of clay. Add the same amount of water to each jar and watch to see where the water goes. The experiment depicts how different soil compositions allow natural gas to flow in and to become trapped underground.
Another version of making gas is more basic than the one described in Section 1. In this experiment offered by Oklahoma Energy Resources Board, you make gas by putting organic materials (beef, lettuce and pond water) into a bottle and placing a balloon over the mouth of the bottle. Let it sit for a few days in a warm place and observe what happens.
This experiment teaches you how natural gas travels. First, make a map of your home. Find the gas appliances in your home and draw each in the appropriate room on the map. Then find the gas meter and mark where it is on the map. Draw where you think the gas pipes go to connect the meter with the appliances. Make another map to illustrate how the natural gas gets from under the ground to your house. Use the information and drawings on the "Natural Gas Distribution" website to help you.