1. Unit 1 Lesson 3 Scientific Investigations Copyright © Houghton Mifflin Harcourt Publishing Company

2. Unit 1 Lesson 3 Scientific Investigations Florida Benchmarks Copyright © Houghton Mifflin Harcourt Publishing Company SC.8.N.1.1 Define a problem from the eighth grade curriculum using appropriate reference materials to support scientific understanding, plan and carry out scientific investigations of various types, such as systematic observations or experiments, identify variables, collect and organize data, interpret data in charts, tables, and graphics, analyze information, make predictions, and defend conclusions.

3. Unit 1 Lesson 3 Scientific Investigations Florida Benchmarks Copyright © Houghton Mifflin Harcourt Publishing Company SC.8.N.1.2 Design and conduct a study using repeated trials and replication. SC.8.N.1.4 Explain how hypotheses are valuable if they lead to further investigations, even if they turn out not to be supported by the data. SC.8.N.1.5 Analyze the methods used to develop a scientific explanation as seen in different fields of science.

4. Unit 1 Lesson 3 Scientific Investigations Florida Benchmarks Copyright © Houghton Mifflin Harcourt Publishing Company SC.8.N.1.6 Understand that scientific investigations involve the collection of relevant empirical evidence, the use of logical reasoning, and the application of imagination in devising hypotheses, predictions, explanations and models to make sense of the collected evidence. LA.6.4.2.2 The student will record information (e.g., observations, notes, lists, charts, legends) related to a topic, including visual aids to organize and record information and include a list of sources used.

5. Testing, Testing, 1, 2, 3 Copyright © Houghton Mifflin Harcourt Publishing Company 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. Unit 1 Lesson 3 Scientific Investigations

6. 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. Copyright © Houghton Mifflin Harcourt Publishing Company Unit 1 Lesson 3 Scientific Investigations

7. 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. Copyright © Houghton Mifflin Harcourt Publishing Company Unit 1 Lesson 3 Scientific Investigations

8. 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. Copyright © Houghton Mifflin Harcourt Publishing Company Unit 1 Lesson 3 Scientific Investigations

9. 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. Copyright © Houghton Mifflin Harcourt Publishing Company Unit 1 Lesson 3 Scientific Investigations

10. 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. Copyright © Houghton Mifflin Harcourt Publishing Company Unit 1 Lesson 3 Scientific Investigations

11. 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. Copyright © Houghton Mifflin Harcourt Publishing Company Unit 1 Lesson 3 Scientific Investigations

12. Many Methods Copyright © Houghton Mifflin Harcourt Publishing Company 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. Unit 1 Lesson 3 Scientific Investigations

13. What are some scientific methods? 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. Copyright © Houghton Mifflin Harcourt Publishing Company Unit 1 Lesson 3 Scientific Investigations

14. What are some scientific methods? 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. Copyright © Houghton Mifflin Harcourt Publishing Company Unit 1 Lesson 3 Scientific Investigations

15. What are some scientific methods? 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. Copyright © Houghton Mifflin Harcourt Publishing Company Unit 1 Lesson 3 Scientific Investigations

16. Life Lessons Copyright © Houghton Mifflin Harcourt Publishing Company 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. Unit 1 Lesson 3 Scientific Investigations

17. 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. Copyright © Houghton Mifflin Harcourt Publishing Company Unit 1 Lesson 3 Scientific Investigations

18. High Quality Copyright © Houghton Mifflin Harcourt Publishing Company 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. Unit 1 Lesson 3 Scientific Investigations

19. 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. Copyright © Houghton Mifflin Harcourt Publishing Company Unit 1 Lesson 3 Scientific Investigations

20. What are some characteristics of good scientific investigations? Copyright © Houghton Mifflin Harcourt Publishing Company Unit 1 Lesson 3 Scientific Investigations

21. 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. Copyright © Houghton Mifflin Harcourt Publishing Company Unit 1 Lesson 3 Scientific Investigations