Easy explanation of how science works, for 6th to 10th graders. Comments and corrections are welcome (English is not my first language). Thank you!

1. The scientific method

2. 1. I observe a natural phenomenon
A natural phenomenon is not just an object: rather, it is something happening or changing in nature

3. 2. I ask myself a question about some aspects of that phenomenon, often about cause–effect relationships
Why?

4. 3. I propose a hypothesis: that is, an educated guess, a possible answer to that question.
Maybe,it’s because...

5. A hypothesis is just an attempt, and it requires both imagination and intelligence: the only condition is that it should be possible to test it by doing experiments.
3. I propose a hypothesis: that is, an educated guess, a possible answer to that question.

6. If my hypothesis cannot be tested in some sort of experiments, I am no longer using the scientific method correctly.
3. I propose a hypothesis: that is, an educated guess, a possible answer to that question.

7. 4. I design an experiment which can tell if my hypothesis is right or wrong.

8. My experiment must be carefully designed so it can give reliable answers about my hypothesis: that is, its results should clearly show if my hypothesis is right or wrong!
4. I design an experiment which can tell if my hypothesis is right or wrong.

9. This is the most difficult step in scientific research. A good scientist, a really creative and innovative one, finds simple and brilliant ways to test his hypothesis through experiments.
4. I design an experiment which can tell if the hypothesis is right or wrong.

10. Alexander Fleming
4. I design an experiment which can tell if my hypothesis is right or wrong.
Do you know my story?

11. 5. I run my experiment and collect quantitative data out of it.

12. The results of my experiment must expressed by measures. Science is all about numbers!
5. I run my experiment and collect quantitative data out of it.

13. 6. I examine the results of my experiment and compare them with those expected if my hypothesis was right.

14. 6. I examine the results of my experiment and compare them with those expected if my hypothesis was right.
There are only two possibilities: either my data tell that my hypothesis is right or they show that it is wrong…
And both are fine!

15. 6. I examine the results of my experiment and compare them with those expected if my hypothesis was right.
In science, hypotheses proven wrong are not a failure.
On the contrary, they are very useful.
They are the only certain knowledge that the scientific method allows:
in science, you can be absolutely sure only about something that is proven false.

16. If it disagrees with experiment, it’s wrong. In that simple statement is the key to science. It doesn’t make any difference how beautiful your guess is, it doesn’t matter how smart you are who made the guess, or what [your] name is… If it disagrees with experiment, it’s wrong. That’s all there is to it.
Richard Feynman
»

17. 7. If my hypothesis was proven wrong by the experimental data, it is discarded or (more often) modified.

18. The same experiments are repeated again and again in the same way, but also changing some experimental conditions, or using different instruments.
8. If my hypothesis was proven right by the experimental data, new experiments are carried out.

19. Meanwhile, I report my results to the other scientists working on the same field in the world, and some of them will carry out the same experiments, also to check that I reported them correctly (and that I did not cheat!)
8. If my hypothesis was proven right by the experimental data, new experiments are carried out.

20. 9. If a particular hypothesis has always been proven right, under all tested conditions and with all the instruments available, it eventually becomes a law or a theory.

21. The word “law” is more used in physics, chemistry and astronomy …
9. If a particular hypothesis has always been proven right, under all tested conditions and with all the instruments available, it eventually becomes a law or a theory.

22. …while the term “theory” is mainly used in biology and geology.
9. If a particular hypothesis has always been proven right, under all tested conditions and with all the instruments available, it eventually becomes a law or a theory.

23. Please notice that in everyday language the words “hypothesis” and “theory” are considered having almost the same meaning, while in science they refer to very different things!
9. If a particular hypothesis has always been proven right, under all tested conditions and with all the instruments available, it eventually becomes a law or a theory.

24. The scientific method can be used only to study natural phenomena regarding matter and/or energy.
Each field of study follows its own method!

25. …This does not mean that only matter and energy exist, but it means that the non-material things must be studied using some different methods.
Each field of study follows its own method!

26. Art, music, history, philosophy, psychology, economics, politics... they all study non-material things and facts, and they all have their own method, different from the scientific method.
Each field of study follows its own method!

27. In science, contrary to popular belief, absolute certainty can never be reached…
Does science produce truth?

28. …because only one experiment (if confirmed) is enough to prove a hypothesis wrong, even if thousands of previous ones had shown it as being right. Well-established laws and theories can be overturned, too.
Does science produce truth?

29. Scientific knowledge is a body of statements of varying degrees of certainty — some most unsure, some nearly sure, but none absolutely certain.
Richard Feynman

30. I am among those who think that science has great beauty.
A scientist in his laboratory is not only a technician: he is also a child placed before natural phenomena which impress him like a fairy tale.
If I see anything vital around me, it is precisely that spirit of adventure, which seems indestructible and is akin to curiosity.
Marie Curie

31. Isaac Newton
I do not know what I may appear to the world; but to myself I seem to have been only like a boy playing on the seashore, and diverting myself in now and then finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me.