hypothesis science definition kid

• Ask a question
• Gather information and observe (research)
• Make a hypothesis (guess the answer)
• Experiment and test your hypothesis
• Analyze your test results
• Modify your hypothesis, if necessary
• Present a conclusion
• Retest (often done by other scientists)

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Hypothesis: A Science Process Skill

January 25, 2021 By Janice VanCleave

A Hypothesis is a Well Thoughtout Prediction.

Yes, asking groups of kids to guess what will happen can be fun. But, expecting a hypothesis for every experiment defeats the purpose for this science process skill.  A  hypothesis  relys on observations that have been previously made. Hypothesis are often called “educated” guesses. Please don’t require kids to give a hypothesis unless it can be based on previous knowledge.  In other words, a hypothesis must be based on  schema , which is previously learned information.

Using an Exploratory Experiment to provide needed schema for a hypothesis. 

Research  is any method used to learn more about a topic. Reading books, magazines as well as online sources and everyday observations of the world around you are good research methods. I suggest that research include exploratory experiments, such as those found in the science book shown. The following exploratory experiment was taken from , “201 Awesome, Magical, Bizarre & Incredible Experiments.” My intention in writing this and other experiment books was to provide fun experiments requiring around the house materials or materials easily found locally. These are exploratory experiments.

FYI:  My books are sold on Amazon as well as other online books suppliers. If you sell my books contact me and I will add a link to your website.

Facts:  Provide information that kids may not be familiar with before introducing the experiment.

• Pressure is the force pressing against a surface.
• Gas molecules move in a straight line until they collide with each other or their container. When colliding, the gas molecules, much like balls striking a wall changes direction and continues moving. Unlike a ball, each gas molecule collides, changes direction and continue at the same speed as before its collision.

 Exploratory Experiment #141 Increasing

Problem: How does temperature affect air pressure? Materials: empty glass soda bottle (any glass bottle with a small mouth) 9-inch (23-cm) round balloon

Something More

Now that kids are engaged –have their schema turned on– introduce a problem related to the previous exploratory experiment.

4. Observe and record the appearance of the balloon over the bottle.

5. Place the open bottle and the bottle with the balloon in a freezer for 15 or more minutes. Note: You can sit the bottles in an ice chest with ice. Make sure both bottles are equally cooled and the chest is closed.  Again, it is important for the air surrounding the bottles to be cold.

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Scientific Method For Kids With Examples

Kids have questions about the world around them every day, and there is so much to learn through experimentation with simple materials. You can begin using the scientific method with elementary kids. Below we’ll share with you how and when to introduce the scientific method, the steps of the scientific method, and some easy scientific method experiments. There are so many great ways to enjoy science projects with kids!

What Is The Scientific Method?

The scientific method is a process or method of research. A problem is identified, information about the problem is gathered, a hypothesis or question is formulated from the information, and the hypothesis is put to the test with an experiment to prove or disprove its validity.

Sounds heavy… What in the world does that mean?!? It means you don’t need to try and solve the world’s biggest science questions! The scientific method is all about studying and learning things right around you.

As children develop practices that involve creating, gathering data evaluating, analyzing, and communicating, they can apply these critical thinking skills to any situation.

Note: The use of the best Science and Engineering Practices is also relevant to the topic of using the scientific method. Read more here and see if it fits your science planning needs.

Can Young Kids Use the Scientific Method?

Kids are great scientists at any age, and can use the scientific method in context to what they are learning. It can be adapted for any age!

The scientific method is a valuable tool for introducing kids to a logical way to solve scientific problems. Scientists use the scientific method to study, learn, and come up with an answer!

The scientific method is a process that helps double-check that answers are correct and the correct results are obtained through careful planning. Sometimes the guesses and questions change as you run your experiments.

Kids can use the scientific method too on questions that are relevant to them!

Let’s break the scientific method for kids down into six parts, and you can quickly see how each can be incorporated into your next science experiment.

What Are The Steps In The Scientific Method?

• Make initial observations.
• Come up with a question of interest that is based on the observations.
• Develop a hypothesis or prediction to go along with the question.
• Experiment and test.
• Gather and record results of tests and experiments and draw conclusions.
• Share and discuss results.

Whoa… Wait A  Minute! That sounds like a lot for a young kid!

You are correct. Depending on your kid’s abilities, following all the scientific method steps precisely will not go well. Someone will get frustrated, bored, and turned off by just how cool science can be. We do not want that to happen!

Using The Scientific Method For Preschool and Kindergarten

Use the scientific method steps as a guideline in the back of your mind. You can cover most of the steps by talking with your kids about…

• What do they think will happen?
• What is happening ?
• What happened compared to what they thought would happen ?

No writing is required! It’s also best to pick pretty straightforward ideas that aren’t overly involved or complicated to set up and test. Kids always have burning questions and “what ifs.”

See if you can tackle their next “what if” using the scientific method by listening carefully to their conversations. You can even have them keep a journal with their “what if” questions for your next science time.

Learn more about Science Activities For Preschoolers and Kindergarten Science Experiments .

Now on to how to apply the scientific method for elementary kiddos and beyond.

Scientific Method Steps In Action

Learn more about the steps of the scientific method below, which are great for science at home with your kids or in the classroom! We have also included some simple scientific method experiments for you to enjoy.

Ice Science Experiments are perfect for this! Try these 3 today !

STEP 1: Make Observations

Tons of everyday activities would make for cool science experiments using the scientific method. Listen to what your kids talk about and see happening. My son noticed that ice melted pretty fast in his water.

Observation is simply noticing what’s happening through our senses or with tools like a magnifying glass. Observation is used to collect and record data, enabling scientists to construct and test hypotheses and theories.

Learn more about observations in science.

STEP 2: Come Up With A Question 

Your kids’ observations should lead to some sort of question. For my son and his ice observations, he came up with questions. Does ice melt faster in different liquids? His curiosity about what happens to the ice in liquids is a simple science experiment perfect for using the scientific method.

Next! Do some research and come up with ideas!

STEP 3: Develop A Prediction or Hypothesis

You have made your observations, you have your question, and now you need to make a prediction about what you think will happen.

A prediction is a guess at what might happen in an experiment based on observation or other information.

A hypothesis is not simply a guess! It’s a statement of what you believe will happen based on the information you have gathered.

My son hypothesizes that ice will melt faster in juice than in water.

STEP 4: Conduct An Experiment

We made a prediction that ice will melt faster in juice than it will in water, and now we have to test our hypothesis. We set up an experiment with a glass of juice, a glass of water, and an ice cube for each.

For the best experiments, only one thing should change! All the things that can be changed in a science experiment are called variables. There are three types of variables; independent, dependent, and controlled.

The independent variable is the one that is changed in the experiment and will affect the dependent variable. Here we will use different types of liquids to melt our ice cube in.

The dependent variable is the factor that is observed or measured in the experiment. This will be the melting of the ice cubes. Set up a stopwatch or set a time limit to observe the changes!

The controlled variable stays constant in the experiment. The liquids should be roughly the same temperature (as close as possible) for our ice melting experiment and measured to the same amount. So we left them out to come to room temperature. They could also be tested right out of the fridge!

You can find simple science experiments here with dependent and controlled variables.

STEP 5: Record Results and Draw Conclusions

Make sure to record what is happening as well as the results—note changes at specific time intervals or after one set time interval.

For example…

• Record when each ice cube is completely melted.
• Add drawings if you wish of the setup up and the end results.
• Was your prediction accurate? If it was inaccurate, record why.
• Write out a final conclusion to your experiment.

STEP 6: Communicate Your Results

This is the opportunity to talk about your hypothesis, experiment, results, and conclusion!

ALTERNATIVE IDEAS: Switch out an ice cube for a lollipop or change the liquids using vinegar and cooking oil.

Now you have gone through the steps of the scientific method, read on for more fun scientific method experiments to try!

Free printable scientific method worksheets!

Fun Scientific Method Experiments

Sink or float experiment.

A Sink or Float experiment is great for practicing the steps of the scientific method with younger kids.

Grab this FREE printable sink or float experiment

Here are a few of our favorite scientific method experiments, which are great for elementary-age kids . Of course, you can find tons more awesome and doable science projects for kids here!

Magic Milk Experiment

Start with demonstrating this delightful magic milk experiment. Then get kids to apply the steps of the scientific method by coming up with a question to investigate. What happens when you change the type of milk used?

What Dissolves In Water

Investigate  what solids dissolve in water  and what do not. Here’s a super fun science experiment for kids that’s very easy to set up! Learn about solutions, solutes, and solvents through experimenting with water and common kitchen ingredients.

Apple Browning Experiment

Investigate how to keep apples from turning brown with this apple oxidation experiment . What can you add to cut apples to stop or slow the oxidation process?

Freezing Water Experiment

Will it freeze? What happens to the freezing point of water when you add salt?

Viscosity Experiment

Learn about the viscosity of fluids with a simple  viscosity experiment . Grab some marbles and add them to different household liquids to find out which one will fall to the bottom first. 

Seed Germination Experiment

Set up a simple seed germination experiment .

Catapult Experiment

Make a simple popsicle stick catapult and use one of our experiment ideas to investigate from rubber band tension to changes in launch angle and more. How far can you fling your objects? Take measurements and find out.

Floating Orange

Investigate whether an orange floats or sinks in water, and what happens if you use different types of oranges. Learn about buoyancy and density with a simple ingredient from the kitchen, an orange.

Bread Mold Experiment

Grow mold on bread for science, and investigate how factors such as moisture, temperature, and air affect mold growth. 

Eggshell Strength Experiment

Test how strong an egg is with this eggshell strength experiment . Grab some eggs, and find out how much weight an egg can support.

Free Printable Science Fair Starter Guide

Are you looking to plan a science fair project, make a science fair board, or want an easy guide to set up science experiments?

Learn more about prepping for a science fair and grab this free printable science fair project pack here!

If you want a variety of science fair experiments with instructions, make sure to pick up a copy of our Science Project Pack in the shop.

Bonus STEM Projects For Kids

STEM activities include science, technology, engineering, and mathematics. As well as our kids science experiments, we have lots of fun STEM activities for you to try. Check out these STEM ideas below…

• Building Activities
• Engineering Projects For Kids
• What Is Engineering For Kids?
• Coding Activities For Kids
• STEM Worksheets
• Top 10 STEM Challenges For Kids

Printable Science Projects Pack

If you’re looking to grab all of our printable science projects in one convenient place plus exclusive worksheets and bonuses like a STEAM Project pack, our Science Project Pack is what you need! Over 300+ Pages!

• 90+ classic science activities  with journal pages, supply lists, set up and process, and science information.  NEW! Activity-specific observation pages!
• Best science practices posters  and our original science method process folders for extra alternatives!
• Be a Collector activities pack  introduces kids to the world of making collections through the eyes of a scientist. What will they collect first?
• Know the Words Science vocabulary pack  includes flashcards, crosswords, and word searches that illuminate keywords in the experiments!
• My science journal writing prompts  explore what it means to be a scientist!!
• Bonus STEAM Project Pack:  Art meets science with doable projects!
• Bonus Quick Grab Packs for Biology, Earth Science, Chemistry, and Physics

19 Comments

A great post and sure to help extend children’s thinking! I would like to download the 6 steps but the blue download button doesn’t seem to be working for me.

Thank you! All fixed. You should be able to download now!

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it is so great, thanks a lot.

This helped for a science project.Thanks so much.

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Hypothesis Definition (Science)

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A hypothesis is an explanation that is proposed for a phenomenon. Formulating a hypothesis is a step of the scientific method .

Alternate Spellings: plural: hypotheses

Examples: Upon observing that a lake appears blue under a blue sky, you might propose the hypothesis that the lake is blue because it is reflecting the sky. One alternate hypothesis would be that the lake is blue because water is blue.

Hypothesis Versus Theory

Although in common usage the terms hypothesis and theory are used interchangeably, the two words mean something different from each other in science. Like a hypothesis, a theory is testable and may be used to make predictions. However, a theory has been tested using the scientific method many times. Testing a hypothesis may, over time, lead to the formulation of a theory.

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A hypothesis is a proposed explanation for some event or problem. For a scientific hypothesis, the scientific method requires that one can test it. [1] [2]

• 2 Statistics
• 3 Hypothesis Media
• 4 Related pages
• 5 References
• 6 Other websites

In the early 17th century, Cardinal Bellarmine gave a well known example of the older sense of the word in his warning to Galileo : that he must not treat the motion of the Earth as a reality, but merely as a hypothesis.

Today, a hypothesis refers to an idea that needs to be tested . A hypothesis needs more work by the researcher in order to check it. A tested hypothesis that works may become part of a theory —or become a theory itself. The testing should be an attempt to prove that the hypothesis is wrong. That is, there should be a way to falsify the hypothesis, at least in principle if not in practice.

People often call a hypothesis an "educated guess".

Experimenters may test and reject several hypotheses, before solving the problem or reaching a satisfactory theory.

A 'working hypothesis' is just a rough kind of hypothesis that is provisionally accepted as a basis for further research. [5] The hope is that a theory will be produced, even if the hypothesis ultimately fails. [6] [7]

Hypotheses are especially important in science. Several philosophers have said that without hypotheses, there could be no science. [8] In recent years, philosophers of science have tried to integrate the various approaches to testing hypotheses (and the scientific method in general), to form a more complete system. The point is that hypotheses are suggested ideas , which are then tested by experiments or observations .

In statistics , people talk about correlation : correlation is how closely related two events or phenomena are. A proposition (or hypothesis) that two events are related cannot be tested in the same way as a law of nature can be tested. An example would be to see if some drug is effective to treat a given medical condition. Even if there is a strong correlation that indicates that this is the case, some samples would still not fit the hypothesis.

There are two hypotheses in statistical tests, called the null hypothesis , often written as [math]\displaystyle{ H_0 }[/math] , and the alternative hypothesis , often written as [math]\displaystyle{ H_a }[/math] . [9] The null hypothesis states that there is no link between the phenomena, [10] and is usually assumed to be true until it can be proven wrong beyond a reasonable doubt. [11] The alternative hypothesis states that there is some kind of link. It is usually the opposite of the null hypothesis, and is what one would conclude if null hypothesis is rejected. [12] The alternative hypothesis may take several forms. It can be two-sided (for example: there is some effect, in a yet unknown direction) or one-sided (the direction of the supposed relation, positive or negative, is fixed in advance). [11]

Hypothesis Media

The hypothesis of Andreas Cellarius , showing the planetary motions in eccentric and epicyclical orbits .

Related pages

• Falsifiability
• Gaia hypothesis
• Null hypothesis
• Occam's razor
• Statistical hypothesis test
• Thought experiment
• ↑ The term comes from the Greek , hypotithenai meaning "to put under" or "to suppose".
• ↑ Bunge, Mario 1967. Scientific research I: the search for system . Berlin: Springer Verlag, Chapter 5, p222.
• ↑ Richard Feynman (1965) The character of physical law . p156
• ↑ Oxford Dictionary of Sports Science & Medicine Eprint via Answers.com
• ↑ See in "hypothesis", Century Dictionary Supplement , v. 1, 1909, New York: Century Company. Reprinted, v. 11, p. 616 (via Internet Archive ) of the Century Dictionary and Cyclopedia , 1911.
• ↑ Schick, Theodore; Vaughn, Lewis (2002). How to think about weird things: critical thinking for a New Age . Boston: McGraw-Hill Higher Education. ISBN   0-7674-2048-9 .
• ↑ Medawar P.B. & J.S. 1983. Aristotle to zoos: a philosophical dictionary of biology . Harvard University Press, p148. ISBN   0-674-04537-8
• ↑ "List of Probability and Statistics Symbols" . Math Vault . 2020-04-26 . Retrieved 2020-09-22 .
• ↑ or that the link does not have the form given by the alternative hypothesis
• ↑ 11.0 11.1 "Null and Alternative Hypotheses | Introduction to Statistics" . courses.lumenlearning.com . Retrieved 2020-09-22 .
• ↑ "Introductory Statistics: Null and Alternative Hypotheses" . opentextbc.ca . Archived from the original on June 11, 2021 . Retrieved September 22, 2020 .

Other websites

• Research and evaluation glossary
• Analysis and synthesis - on scientific method, based on a study by Bernhard Riemann from the Swedish Morphological Society

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Definition of hypothesis

Did you know.

The Difference Between Hypothesis and Theory

A hypothesis is an assumption, an idea that is proposed for the sake of argument so that it can be tested to see if it might be true.

In the scientific method, the hypothesis is constructed before any applicable research has been done, apart from a basic background review. You ask a question, read up on what has been studied before, and then form a hypothesis.

A hypothesis is usually tentative; it's an assumption or suggestion made strictly for the objective of being tested.

A theory , in contrast, is a principle that has been formed as an attempt to explain things that have already been substantiated by data. It is used in the names of a number of principles accepted in the scientific community, such as the Big Bang Theory . Because of the rigors of experimentation and control, it is understood to be more likely to be true than a hypothesis is.

In non-scientific use, however, hypothesis and theory are often used interchangeably to mean simply an idea, speculation, or hunch, with theory being the more common choice.

Since this casual use does away with the distinctions upheld by the scientific community, hypothesis and theory are prone to being wrongly interpreted even when they are encountered in scientific contexts—or at least, contexts that allude to scientific study without making the critical distinction that scientists employ when weighing hypotheses and theories.

The most common occurrence is when theory is interpreted—and sometimes even gleefully seized upon—to mean something having less truth value than other scientific principles. (The word law applies to principles so firmly established that they are almost never questioned, such as the law of gravity.)

This mistake is one of projection: since we use theory in general to mean something lightly speculated, then it's implied that scientists must be talking about the same level of uncertainty when they use theory to refer to their well-tested and reasoned principles.

The distinction has come to the forefront particularly on occasions when the content of science curricula in schools has been challenged—notably, when a school board in Georgia put stickers on textbooks stating that evolution was "a theory, not a fact, regarding the origin of living things." As Kenneth R. Miller, a cell biologist at Brown University, has said , a theory "doesn’t mean a hunch or a guess. A theory is a system of explanations that ties together a whole bunch of facts. It not only explains those facts, but predicts what you ought to find from other observations and experiments.”

While theories are never completely infallible, they form the basis of scientific reasoning because, as Miller said "to the best of our ability, we’ve tested them, and they’ve held up."

• proposition
• supposition

hypothesis , theory , law mean a formula derived by inference from scientific data that explains a principle operating in nature.

hypothesis implies insufficient evidence to provide more than a tentative explanation.

theory implies a greater range of evidence and greater likelihood of truth.

law implies a statement of order and relation in nature that has been found to be invariable under the same conditions.

Examples of hypothesis in a Sentence

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'hypothesis.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Greek, from hypotithenai to put under, suppose, from hypo- + tithenai to put — more at do

1641, in the meaning defined at sense 1a

Phrases Containing hypothesis

• counter - hypothesis
• nebular hypothesis
• null hypothesis
• Whorfian hypothesis
• planetesimal hypothesis

Articles Related to hypothesis

This is the Difference Between a...

This is the Difference Between a Hypothesis and a Theory

In scientific reasoning, they're two completely different things

Dictionary Entries Near hypothesis

hypothermia

hypothesize

Cite this Entry

“Hypothesis.” Merriam-Webster.com Dictionary , Merriam-Webster, https://www.merriam-webster.com/dictionary/hypothesis. Accessed 16 Mar. 2024.

Kids Definition

Kids definition of hypothesis, medical definition, medical definition of hypothesis, more from merriam-webster on hypothesis.

Nglish: Translation of hypothesis for Spanish Speakers

Britannica English: Translation of hypothesis for Arabic Speakers

Britannica.com: Encyclopedia article about hypothesis

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Scientific theory facts for kids

In everyday speech, the word "theory" is used as a "best guess". In modern science , a scientific theory is a tested and expanded hypothesis that explains many experiments. It fits ideas together in a framework. If anyone finds a case where all or part of a scientific theory is false , then that theory is either changed or thrown out.

An example of a scientific theory that underwent many changes is the germ theory of disease . In ancient times, people believed that diseases were caused by the gods, or by curses, or by improper behavior. Germs ( microorganisms ) were unknown, because germs are too small to see. With the invention of the microscope , germs were discovered, and the germ theory of disease was proposed. Thanks to the germ theory of disease, many diseases can now be cured. However, the germ theory of disease had to be modified, because some diseases are not caused by germs. The flu and scurvy are examples of diseases that are not caused by bacteria, but viruses or poor nutrition. Scientists modified the germ theory of disease, so that today we would state that theory as "Some diseases are caused by germs".

To be a scientific theory, a theory must be tested a large number of times, by different scientists in different places, and must pass the test every time. The theory must be stated exactly, sometimes using mathematics . And it must fit in with all of the other scientific theories. Science has many branches. Physics , chemistry , biology , geology , and astronomy are some of the major branches of science. A scientific theory in one branch of science must hold true in all of the other branches of science. For example, the atomic theory of matter, that all matter is made up of atoms, was discovered using physics, but the chemicals used in chemistry, the living tissue used in biology, the rocks studied in geology, and the planets studied in astronomy are all made up of atoms. The atomic theory of matter holds in every area of science.

Sometimes scientists come up with a theory that is wrong. The discovery of an exception to a scientific theory is a major event, and a scientist can become famous by discovering an exception to a rule. Einstein became famous for his theory of relativity, which found an exception to Isaac Newton's laws of motion. Newton's theory, which had been accepted for hundreds of years, had to be changed, and has been changed.

Here is a list of some of the major theories of modern science. These theories have been tested thousands of times, and no exception has been found.

• The atomic theory of matter: all matter is made up of atoms.
• The law of conservation of mass and energy : in chemical and physical reactions, mass and energy stay the same, in atomic reactions, mass is changed to energy or energy to mass according to the formula E = mc 2 .
• The cell theory of living things: all living things are made up of cells.
• The tectonic theory of geology: the surface of the earth is composed of tectonic plates, which move slowly.
• The periodic table of elements: atoms are distinguished by their atomic number and atomic weight, and can be arranged in a table which illustrates their properties.
• The theory of relativity : scientific laws hold in different frames of reference.
• Quantum theory : the smallest amount of energy is a "quantum unit", and all energy comes in multiples of this amount.
• The theory of evolution : It explains how living things changed over a long time, and how they have come to be the way they are.

Related pages

• Philosophy of science
• Scientific method

Images for kids

The first observation of cells , by Robert Hooke , using an early microscope . This led to the development of cell theory .

In quantum mechanics , the electrons of an atom occupy orbitals around the nucleus . This image shows the orbitals of a hydrogen atom ( s , p , d ) at three different energy levels (1, 2, 3). Brighter areas correspond to higher probability density.

• This page was last modified on 16 October 2023, at 16:53. Suggest an edit .