Scientific investigations may take many different forms, including observing what things are like or what is happening somewhere, collecting specimens for analysis, and doing experiments.
Learning Goal 2a
Because we expect science investigations that are done the same way to produce the same results, when they do not, it is important to try to figure out why.
Learning Goal 2b
One reason for following directions carefully and for keeping records of one's work is to provide information on what might have caused differences in investigations.
Learning Goal 3a
Scientists' explanations about what happens in the world come partly from what they observe, partly from what they think.
Learning Goal 3bc
Sometimes scientists have different explanations for the same set of observations. That usually leads to their making more observations to resolve the differences.
Learning Goal 4
Scientists do not pay much attention to claims about how something they know about works unless the claims are backed up with evidence that can be confirmed, along with a logical argument.
For Grades: 6-8
Learning Goal 1a
Scientists differ greatly in what phenomena they study and how they go about their work.
Learning Goal 1b
Scientific investigations usually involve the collection of relevant data, the use of logical reasoning, and the application of imagination in devising hypotheses and explanations to make sense of the collected data.
Learning Goal 2ab
If more than one variable changes at the same time in an experiment, the outcome of the experiment may not be clearly attributable to any one variable. It may not always be possible to prevent outside variables from influencing an investigation (or even to identify all of the variables).
Learning Goal 2c
Collaboration among investigators can often lead to research designs that are able to deal with situations where it is not possible to control all of the variables.
Learning Goal 3ab
What people expect to observe often affects what they actually do observe. Strong beliefs about what should happen in particular circumstances can prevent them from detecting other results.
Learning Goal 3cd
Scientists know about the danger of prior expectations to objectivity and take steps to try and avoid it when designing investigations and examining data. One safeguard is to have different investigators conduct independent studies of the same questions.
For Grades: 9-12
Learning Goal 1
Investigations are conducted for different reasons, including to explore new phenomena, to check on previous results, to test how well a theory predicts, and to compare theories.
Learning Goal 2
Hypotheses are widely used in science for choosing what data to pay attention to and what additional data to seek, and for guiding the interpretation of the data (both new and previously available).
Learning Goal 3
Sometimes, scientists can control conditions in order to obtain evidence. When that is not possible, practical, or ethical, they try to observe as wide a range of natural occurrences as possible to discern patterns.
Learning Goal 4
There are different traditions in science about what is investigated and how, but they all share a commitment to the use of logical arguments based on empirical evidence.
Learning Goal 5
Scientists in any one research group tend to see things alike, so even groups of scientists may have trouble being entirely objective about their methods and findings. For that reason, scientific teams are expected to seek out the possible sources of bias in the design of their investigations and in their data analysis. Checking each other's results and explanations helps, but that is no guarantee against bias.
Learning Goal 6a
In the short run, new ideas that do not mesh well with mainstream ideas in science often encounter vigorous criticism.
Learning Goal 6b
In the long run, theories are judged by the range of observations they explain, how well they explain observations, and how useful they are in making accurate predictions.
Learning Goal 7
New ideas in science are limited by the context in which they are conceived; are often rejected by the scientific establishment; sometimes spring from unexpected findings; and usually grow slowly, through contributions from many investigators.
Learning Goal 8
Scientists' nationality, sex, ethnic origin, age, political convictions, and so on may incline them to look for or emphasize one or another kind of evidence or interpretation.
Learning Goal 9
To be useful, a hypothesis should suggest what evidence would support it and what evidence would refute it. A hypothesis that cannot, in principle, be put to the test of evidence may be interesting, but it may not be scientifically useful.
Learning Goal 10
Bias attributable to the investigator, the sample, the method, or the instrument may not be completely avoidable in every instance, but scientists want to know the possible sources of bias and how bias is likely to influence evidence.
Learning Goal 11
To avoid biased observations, scientific studies sometimes use observers who don't know what the results are "supposed" to be.