Independent Variable Lesson for Kids: Definition & Examples

Instructor: Lindsy Frazer

Dr. Frazer has taught several college level Science courses and has a master's degree in Human Biology and a PhD in Library and Information Science.

An independent variable is an important part of any scientific experiment. Learn what an independent variable is and explore some examples of independent variables in this lesson.

Definition of Independent Variables

Will white chocolate melt faster than dark chocolate? Experiments are used to answer questions like this. Most experiments are set up to see if a change in one factor causes a change in another factor. These factors that can be changed are called variables. There are three main types of variable: independent, dependent and controlled.

The independent variable is the factor in an experiment that the experimenter changes. This variable is not influenced by any other factors in the experiment, but it causes change in other variables. In other words, the independent variable is the cause of change in an experiment. Variables that are changed by the independent variable are called dependent variables. A good experiment only has one independent variable so that the experimenter can be sure that changes to the dependent variable are caused by the independent variable.

The experimenter changes the independent variable and the independent variable causes change in other variables.
independent variable

Soapy Situation: Example 1

Which soap is the best at killing germs? To answer this question, think like a scientist and set up an experiment. You could wash your hands in warm water with soap A and use a microscope to count how many germs are left on your palms. Next, you could wash your hands in warm water with soap B and count the germs left.

Which soap kills the most germs?
soap experiment

What did you- the scientist- change each time you washed your hands? You changed the type of soap you used. So, type of soap is the independent variable. The goal of the experiment was to see if changes in the type of soap used causes changes in the amount of germs killed (the dependent variable).

ExperiMINT: Example 2

Have you ever chewed a piece of mint flavored gum and felt like the inside of your mouth got colder? Do mints really make things colder or does it just feel that way? To answer this question with an experiment you could fill three glasses with water and place one mint in one glass, two mints in another glass and no mints in the third glass. Then, using a thermometer, you could record and compare the temperature of the water in each glass.

To unlock this lesson you must be a Study.com Member.
Create your account

Register for a free trial

Are you a student or a teacher?
I am a teacher
What is your educational goal?

Unlock Your Education

See for yourself why 10 million people use Study.com

Become a Study.com member and start learning now.
Become a Member  Back

Earning College Credit

Did you know… We have over 95 college courses that prepare you to earn credit by exam that is accepted by over 2,000 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? Study.com has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it free for 5 days!
Create An Account