u1l3 - scientific investigations

Unit 1 Lesson 3 Scientific Investigations

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Indiana Standards


• NOS 8.1 Make predictions and develop testable questions based on research and prior knowledge.

• NOS 8.2 Plan and carry out investigations as a class, in small groups or independently often over a period of several class lessons.

• NOS 8.3 Collect quantitative data with appropriate tools or technologies and use appropriate units to label numerical data.


Indiana Standards


• NOS 8.4 Incorporate variables that can be changed, measured or controlled.

• NOS 8.5 Use the principles of accuracy and precision when making measurement.

• NOS 8.6 Test predictions with multiple trials.

• NOS 8.7 Keep accurate records in a notebook during investigations.


Indiana Standards


• NOS 8.8 Analyze data, using appropriate mathematical manipulation as required, and use it to identify patterns and make inferences based on these patterns.

• NOS 8.9 Evaluate possible causes for differing results (valid data).

• NOS 8.10 Compare the results of an experiment with the prediction.

Testing, Testing, 1, 2, 3


What are some parts that make up scientific investigations?• Scientists investigate the natural world through

experiments and observations.

• An experiment is an organized procedure to study something under controlled conditions.

• Observation is the process of obtaining information by using the senses.


What are some parts that make up scientific investigations? • Scientific investigations may also involve the use

of models.

• A model is a representation of an object or system.



What are some parts that make up scientific investigations? • A testable idea or explanation that leads to

scientific investigation is called a hypothesis.

• A scientist may think of a hypothesis after making observations or after reading findings from other scientists’ investigations.

• Hypotheses must be carefully constructed so they can be tested in a practical and meaningful way.



What are some parts that make up scientific investigations? • If an investigation does not support a hypothesis,

it is still useful.

• The information from the investigation can help scientists form a better hypothesis.

• Scientists may go through many cycles of testing and analysis before they arrive at a hypothesis that is supported.



What are some parts that make up scientific investigations? • A variable is any factor that can change in a

scientific investigation.

• An independent variable is the factor that is deliberately manipulated.

• A dependent variable changes as a result of manipulation of one or more independent variables.



What are some parts that make up scientific investigations? • Data are information gathered by observation or

experimentation that can be used in calculating or reasoning.

• This information may be anything that a scientist perceives through the senses or detects using instruments.

• During their investigations, scientists record all their observations, setup, and procedures so that they will not forget anything.



What are some parts that make up scientific investigations? • Scientists analyze data to determine the

relationship between the independent and dependent variables in an investigation.

• Then they draw conclusions about whether the data support the investigation’s hypothesis.



Many Methods


What are some scientific methods?

• Scientists do not always use the same steps or same order of steps in every investigation.

• They may even repeat some steps.



• Consider one possible path that a scientist might follow while conducting an experiment.

• First, the scientist clearly and precisely defines the problem or question that needs to be answered.

• Next, the scientist forms a hypothesis and makes predictions about what will happen in the investigation.




• To test the hypothesis, the investigation must be carefully planned, taking into account the materials and equipment needed.

• The scientist must also decide how the independent variable will change and identify other variables that will be controlled.




• The scientist must also determine how the results of the experiment will be measured.

• The data collected in an investigation must be recorded and properly organized.

• After the data are collected, the scientist may analyze them and draw conclusions about the results.



Life Lessons


How are scientific methods used?

• Science is an ongoing process, as scientific investigations provide evidence that can either support or contradict a hypothesis.

• A hypothesis can be replaced by a new or modified hypothesis after further investigation.

• Thus, scientists are always prepared to modify their understandings of the natural world.


How are scientific methods used?

• Scientific methods are used in physical, life, and earth sciences.

• Scientists carefully choose the setting for an investigation, such as the field or a laboratory.

• Scientists may use models when studying things that are very large, small, or complex.



High Quality


What are some characteristics of good scientific investigations?• Good scientific investigations share some

important characteristics.

• Scientific observations should be well documented and have supporting evidence.

• In an experiment, the variables should be controlled as much as possible.


What are some characteristics of good scientific investigations?• Experiments should be repeated multiple times by

the original investigator.

• All scientific investigations should be replicated by scientists not involved with the original work.

• Before publishing a study, scientific journals ask other scientists to review the article. This is called peer review.



What are some characteristics of good scientific investigations?



How can you evaluate the quality of scientific information?• The most reliable scientific information is

published in scientific journals, but it is often difficult to understand.

• Reliable books are written by scientists and others who are knowledgeable about a particular field.

• Reliable Internet sources are government and academic web pages. Commercial web pages are often unreliable because they are trying to sell something.



u1l3 - scientific investigations

Science

investigations hypothesis

scientists investigations

scientific methods

better hypothesis

quantitative data

numerical data

independent variables

use of models