TheScientificMethod-ScientificMethodSteps

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IntroductiontotheScientificMethodOkay,youneedtocomeupwithascientificresearchprojector

sciencefairproject.Oneoftheobviouschallengesistofindanideafortheproject.Also,youneedscience involved,soyouwillneedtoapplythescientificmethodsomehow.Thescientificmethodcanbestated several ways, but basically it involves looking at the worldaroundyou, comingupwithanexplanation forwhatyouobserve,testingyourexplanationtosee if itcouldbevalid,andtheneitheracceptingyourexplanation(forthetimebeing...afterall,somethingbettermightcomealong!)orrejectingtheexplanationandtryingtocomeupwithabetterone.

Scientific Method StepsThe exact number of steps to thescientificmethoddependsonhowyoubreakupthesteps,buthereisanoverviewofthebasics:

1. Makeobservations.2. Proposeahypothesis.3. Design and perform an experiment to test the

hypothesis.4. Analyze your data to determine whether to

acceptorrejectthehypothesis.5. Ifnecessary,proposeandtestanewhypothesis.

If you are having trouble designing an experiment orevengettinganideaforaproject,startwiththefirststepofthescientificmethod:makeobservations.

ScientificMethodStep1:MakeObservations

A lot of people think that the scientificmethod startswith forming a hypothesis. The reason for this

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misconception may be because many observations aremade informally. After all, when you are looking for aproject idea, you think throughall of the things youhaveexperienced(observationsyouhavemade)andtrytofindone that would be suitable for an experiment. Althoughthe informal variation of Step 1 works, you will have arichersourceofideasifyoupickasubjectandwritedownobservationsuntilatest-ableideacomesup.Forexample,let's say youwant to do an experiment, but youneed anidea. Take what is around you and start writing downobservations. Write down everything! Include colors,timing, sounds, temperatures, light levels... you get theidea.

ScientificMethodStep2:FormulateaHypothesis

Ahypothesisisastatementthatcanbeusedtopredicttheoutcomeoffutureobservations.Thenullhypothesis,orno-difference hypothesis, is a good type of hypothesis totest. This type of hypothesis assumes no differencebetween two states. Here is an example of a nullhypothesis:'therateatwhichgrassgrowsisnotdependentontheamountoflightitreceives'.EvenifIthinkthatlightaffects therateatwhichmygrassgrows (probablynotasmuchasrain,butthat'sadifferenthypothesis),itiseasierto disprove that light has no effect than to get intocomplicateddetailsabout'howmuchlight',or'wavelengthoflight',etc.However,thesedetailscanbecometheirownhypotheses (stated in null form) for furtherexperimentation.Itiseasiesttotestseparatevariables inseparate experiments. In other words, don't test theeffectsof lightandwateratthesametimeuntilafteryou

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havetestedeachseparately.

ScientificMethodStep3:DesignanExperiment

There are many different ways to test a singlehypothesis.IfIwantedtotestthenullhypothesis,'therateof grass growth is not dependent on quantity of light', Iwould have grass exposed to no light (a control group...identical in every way to the other experimental groupsexceptforthevariablebeingtested),andgrasswithlight.I could complicate the experiment by having differinglevelsoflight,differenttypesofgrasses,etc.Letmestressthat the control group can only differ from anyexperimentalgroupswithrespecttotheonevariable.Forexample, inall fairnessIcouldnotcomparegrass inmyyard in the shade and grass in the sun... there are othervariables between the two groups besides light, such asmoisture and probably pH of the soil (where I am it ismore acidic near the trees and buildings, which is alsowhereitisshady).Keepyourexperimentsimple.

ScientificMethodStep4:TesttheHypothesis

In other words, perform an experiment! Your datamight takethe formofnumbers,yes/no,present/absent,or other observations. It is important to keep data that'looks bad'. Many experiments have been sabotaged byresearchers throwing out data that didn't agree withpreconceptions.Keepallofthedata!Youcanmakenotesifsomethingexceptionaloccurredwhenaparticulardatapoint was taken. Also, it is a good idea to write downobservations related to your experiment that aren't

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directlyrelatedtothehypothesis.Theseobservationscouldincludevariablesoverwhichyouhavenocontrol,suchashumidity,temperature,vibrations,etc.,oranynoteworthyhappenings.

Step5:AcceptorRejecttheHypothesis

Formanyexperiments,conclusionsareformedbasedoninformalanalysisofthedata.Simplyasking,'Doesthedata fit the hypothesis', is one way to accept or reject ahypothesis. However, it is better to apply a statisticalanalysis to data, to establish a degree of 'acceptance' or'rejection'. Mathematics is also useful in assessing theeffectsofmeasurementerrorsandotheruncertaintiesinanexperiment.

HypothesisAccepted?ThingstoKeepinMind

Acceptingahypothesisdoesnotguaranteethatitisthecorrecthypothesis!Thisonlymeansthattheresultsofyourexperiment support the hypothesis. It is still possible toduplicate the experiment and get different results nexttime.Itisalsopossibletohaveahypothesisthatexplainsthe observations, yet is the incorrect explanation.Remember, a hypothesis can be disproven, but neverproven!

HypothesisRejected?BacktoStep2

Ifthenullhypothesiswasrejected,thatmaybeasfaras your experiment needs to go. If any other hypothesis

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was rejected, then it is time to reconsider yourexplanation for your observations. At least youwon't bestarting from scratch... you havemore observations anddatathaneverbefore!

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