A key part of scientific discovery is the process or steps that are used to make any discovery. Scientists search for new knowledge with a problem-solving approach known as the scientific method. The scientific method involves four basic steps 1) determining the problem by making observations 2) forming a hypothesis 3) analyzing and testing the hypothesis 4) drawing conclusions. Each of these steps is made up of several other processes or steps.

One way natural events of our world are explained is by using the methods of science. Science is a process that produces a body of knowledge about nature. Using science, people arrive at solutions to problems or questions about the natural world. Science is all the discoveries about the natural world that have been made throughout history. As each generation gathers more information people gradually are learning how the universe works. Science is the process and thinking that is used, it is not the facts and information produced.

A hypothesis is an educated guess about a problem that is based on information obtained by observation. This explanation of a scientific problem is not the final answer because the hypothesis has not been proven to be true. Many times the discovery of more information shows that the first hypothesis is wrong and needs to be changed. When there is more data from experiments or tests to support the explanation, a scientist is more confident that the hypothesis is correct. An explanation backed by results obtained from repeated tests or experiments is a theory. A hypothesis may become a theory when all new information gathered over a long period of time supports it to be true.

In order to solve a problem, you first must determine what it is that you want to know and make observations. Next you form a hypothesis about those observations. Then an experiment or test can be made to see if the hypothesis was correct. To design an experiment, you must decide which things it is that you want to measure or investigate. The changeable factors (the things you don't know) in an experiment are called variables.

If the experiment shows that the hypothesis is wrong, a new hypothesis is formed and a new experiment is made to test the new hypothesis.

Scientists learn things through observing, classifying, inferring, and hypothesizing. With observations that are made when you use your sense of sight, touch, hearing, and maybe your sense of smell or taste, you are making a direct observation. However our senses have limitations. Sometimes we are unable to measure accurately the observations we make without using scientific instruments. Scientific instruments can extend our senses beyond their normal limits. They allow us to make indirect observations.

Scientists make data meaningful by using processes such as classifying. Classifying is the grouping of similar events or objects, based upon the observed properties or characteristics. Scientists can classify substances according to their properties. Different substances have different physical and chemical properties. Physical properties are the features of the object itself and chemical properties are the way a substance reacts with other substances.

The international system for measurements is the International System or SI. It is used by scientists around the world. The SI system is sometimes called the metric system. It is based on the number ten and uses multiples of ten. This means that units can be converted by moving the decimal point.

In the SI system, units of length are based on the meter. Units of liquid volume are based on the liter and units of mass are based on the gram. Mass is the amount of matter in an object. It is usually measured in grams or kilograms. The triple beam balance is used to measure mass. Mass is frequently confused with weight. Weight is the amount of the gravitational force on an object. In the SI system weight is measured in newtons.

When we measure volume, the units are always expressed as cubic units of meters, centimeters, or millimeters. Density is the amount of material in a specific volume of material. To calculate the density we need to know the volume and the mass of the material. Scientifically we define density as the mass of one cubic centimeter of material. The formula for density is mass divided by volume, D=M/V. Different materials and elements have different densities. Rocks have different densities depending upon the kind of rocks. This will be used to explain how mountains are formed and how volcanoes erupt.

Earth science includes many other branches of science to explain the nature for the many processes that affect the Earth. Geology is the study of all the processes affecting the solid part of the Earth. Meteorology is the study of the atmosphere and the weather of the Earth. Oceanography is the study of the oceans and their boundaries. Earth science also uses chemistry to study how the chemicals of materials react with other materials. Earth science also uses biology, the study of living things and hydrology the study of the Earth's water. We also use astronomy, the study of objects in space. An important part of earth science is petrology, the part of geology that deals with rocks and ecology, the study of the environment.