There is no single list called "The Scientific Method." It is a myth.
The rules of a science-fair typically require that students follow THE SCIENTIFIC METHOD, or in other words, hypothesis-experiment-conclusion. The students must propose a hypothesis and test it by experiment. This supposedly is the "Scientific Method" used by all scientists. Supposedly, if you don't follow the rigidly defined "Scientific Method" listed in K-6 textbooks, then you're not doing science. (Some science fairs even ban astronomy and paleontology projects. After all, where's the "experiment" in these?)
Unfortunately this is wrong, and there is no single "Scientific Method" as such. Scientists don't follow a rigid procedure-list called "The Scientific Method" in their daily work. The procedure-list is a myth spread by K-6 texts. It is an extremely widespread myth, and even some scientists have been taken in by it, but this doesn't make it any more real. "The Scientific Method" is part of school and school books, and is not how science in general is done. Real scientists use a large variety of methods (perhaps call them methods of science rather than "The Scientific Method.") Hypothesis / experiment / conclusion is one of these, and it's very important in experimental science such as physics and chemistry, but it's certainly not the only method. It would be a mistake to elevate it above all others. We shouldn't force children to memorize any such procedure list. And we shouldn't use it to exclude certain types of projects from science fairs! If "The Scientific Method" listed in a grade school textbook proves that Astronomy is not a science, then it's the textbook which is wrong, not Astronomy.
"Ask a scientist what he conceives the scientific method to be and he adopts an expression that is at once solemn and shifty-eyed: solemn, because he feels he ought to declare an opinion; shifty-eyed because he is wondering how to conceal the fact that he has no opinion to declare." - Sir Peter Medawar
There are many parts of science that cannot easily be forced into the mold of "hypothesis-experiment-conclusion." Astronomy is not an experimental science, and Paleontologists don't perform Paleontology experiments... so is it not proper Science if you study stars or classify extinct creatures?
Or, if a scientist has a good idea for designing a brand new kind of measurement instrument (e.g. Newton and the reflecting telescope) ...that certainly is "doing science." Humphrey Davy says "Nothing tends so much to the advancement of knowledge as the application of a new instrument." But where is The Hypothesis? Where is The Experiment? The Atomic Force Microscope (STM/AFM) revolutionized science. Yet if a student invented the very first reflector telescope or the very first AFM, wouldn't such a device be rejected from many school science fairs? After all, it's not an experiment, and the lists called "Scientific Method" say nothing about exploratory observation. Some science teachers would reject the STM as science; calling it 'mere engineering,' yet like the Newtonian reflector, the tunneling microscope is a revolution that opened up an entire new branch of science. Since it's instrument-inventing, not hypothesis-testing, should we exclude it as science? Were the creators of the STM not doing science when they came up with that device? In defining Science, the Nobel prize committee disagrees with the science teachers and science fair judges. The researchers who created the STM won the 1986 Nobel prize in physics. I'd say that if someone wins a Nobel prize in physics, it's a good bet that their work qualifies as "science."
Forcing kids to follow a caricature of scientific research distorts science, and it really isn't necessary in the first place.
Another example: great discoveries often come about when scientists notice anomalies. They see something inexplicable during older research, and that triggers some new research. Or sometimes they notice something weird out in Nature; something not covered by modern theory. Isaac Asimov said it well:
"The most exciting phrase to hear in science, the one that heralds new discoveries, is not 'Eureka!' (I found it!) but 'That's funny...' "
This suggests that lots of important science comes NOT from proposing hypotheses or even from performing experiments, but instead comes from unguided observation and curiosity-driven exploration: from sniffing about while learning to see what nobody else can see. Scientific discovery comes from something resembling "informed messing around," or unguided play. Yet the "Scientific Method" listed in textbooks says nothing about this, their lists start out with "form a hypothesis." As a result, educators treat science as deadly serious business, and "messing around" is sometimes dealt with harshly.