Nature of Science Day 2: Nature of Science and Engineering NSE 3-6 MSTP Region 11 Teacher Center Today’s Trainers: Tamara Moore and Selcen Guzey
Nature of Science Goals Share experiences implementing engineering lessons. Develop an understanding of the central tenets of the nature of science. Learn how to implement lessons that highlight tenets of the nature of science.
Engineering Lessons • Put your poster up. • In your handout, you have space to record your observations about others’ engineering activities. • Take 10 minutes then we’ll come back to debrief.
Engineering vs. Science • What is engineering? • What is science? • How are the similar/dissimilar?
Science is … Science refers to a system of acquiring knowledge. This system uses observation and experimentation to describe and explain natural phenomena.
Nature of Science For the following statements, think briefly about the comment and decide whether you agree or disagree. State the rationale for or defend your answer. • There is a single scientific method agreed upon and used by those involved in science. • Because science is based on evidence, it can be used to answer any question. • Imagination and creativity play a significant role in the work of a scientist. • Scientific laws and theories are open to debate and can be changed. • Because science is based on fact, bias does not play a significant role in scientific activities.
Nature of Science: Observations • Please observe setup in the front • Write down your observations • Share your observations with your neighbor
Nature of Science: Observation and Inference • Observation: • Our perception of an object or an event, using as many senses as possible. • Inference: • Reasonable explanation that we construct on the basis of our observations. • Science as a Way of Knowing: • Scientific knowledge is based on observation and inference
Nature of Science: Tricky Tracks You are a group of paleontologists’ called in to examine a set of fossils. What do you observe? What can you infer from your observations?
Nature of Science: Tricky Tracks • Individually make a “T-chart” on a blank piece of paper • Title one column “Observations” and the other “Inferences” • Separate our ideas into observations and inferences
Nature of Science: Tricky Tracks A new piece of the fossil evidence is discovered What do you observe? What can you infer?
Nature of Science: Tricky Tracks A third piece of the fossil record is discovered. Write down your story/explanation for what happened.
Teaching the Nature of Science The activity aims to help students: • Distinguish between observation and inference. • Realize that, based on the same set of evidence (observations, or data), several answers to the same question may be equally valid. Scientific knowledge is partly a product of human inference, imagination, and creativity, even though it is, at least partially, supported by empirical evidence. As such, scientific knowledge is never absolute or certain. This knowledge (including theories and laws) is tentative and subject to change.
Nature of Science: Observations • How can it be that some of us see only one face and not the other? • Is it possible that some scientists may look at the same piece of evidence or set of data and see different things? • The knowledge and expectations with which we approach any phenomenon may affect the way we interpret that phenomenon: Observations are theory-laden
Nature of Science: Fish is Fish • What Lionni’s story tell us about observation and inference? The role of creativity and imagination in science? • What Lionni’s story tell us about how students learn? • new understandings are constructed on a foundation of existing understandings and experiences. • factual information is not enough – need to develop conceptual understanding
Nature of Science: The Role of Hypotheses • What is a hypothesis? • What is a law? • What is a theory? • How are they related?
Nature of Science: Black Box Activities • Investigate the behavior of the black box. • Record your observations in your notebook. • What are the “laws of tube strings”? • Develop a hypothesis to explain the observable behavior of the box. • Test your hypothesis.
Nature of Science: Another Black Box Activity • Rule: You cannot open the box • Investigate the behavior of the black box. • What do you think is inside your black box? • Record your observations in your notebook. • Make inferences about what you think is inside your black box and draw a picture.
Nature of Science: Another Black Box Activity • Meet with a group and discuss the diagram that you drew. • Resolve any disagreements • You will need to come up with one agreed upon diagram. • Choose one person to draw you diagram on the whiteboard.
Nature of Science: Another Black Box Activity • Now that you have seen the models, here are the four options – teacher info.
Nature of Science: Black Box Activities Black-box activities can be used to convey to students appropriate conceptions of many aspects of the NOS. Students can be helped to understand: • The distinction between observation and inference. • That scientific knowledge is partly a product of human inference, imagination, and creativity. • That scientific knowledge is, eventually, empirically based (i.e., based on and/or derived from experiment and observation). • That scientific knowledge (both theories and laws) is tentative and subject to change. • That scientific models (e.g., atom, gene) are not copies of reality. Rather, these models are theoretical entities used to explain natural phenomena.
Should you let the students open the box? • Reasons to not let them: • More like science • Reasons to let them: • Blackbox activities where students build a prototype is a version of reverse engineering. • Why might engineers do something like this?
Nature of Science: Black Box Activities In addition, these activities provide students with opportunities to practice some science process skills. Among these are: • Observing and collecting data. • Inferring, hypothesizing and devising `ways' to test those hypotheses (or inferences). • Constructing models.
Behavior of Magnets and Magnetic Materials The purpose of this laboratory investigation is for you and your group to explore how magnets and magnetic objects behave. Record observations from Demo #1 What generalizing statement/law can we make? Like poles repel and opposite poles attract
Behavior of Magnets and Magnetic Materials What kinds of materials does a magnet affect? Record observations from Demo #2 What generalizing statement/law can we make? Materials that are attracted to a magnet are called ferromagnetic Iron and Nickel are ferromagnetic materials
Behavior of Magnets and Magnetic Materials How do you make a magnet? Testing “rubbed nails” • Place one end of the bar magnet over one end (tip or head) of an unrubbed nail and rub in one direction only to the other end. Then lift the magnet away from the nail and repeat the process a few times, always rubbing in the same direction.
Behavior of Magnets and Magnetic Materials Are rubbed nails the same as magnets? Test behavior of rubbed nails Experiment # 1 Place a rubbed nail on the floater, making sure that other rubbed nails and the magnet are far away. Spin the floating rubbed nail gently, and watch it for at least half a minute until it seems to settle down. Repeat this two or three times.
Behavior of Magnets and Magnetic Materials Experiment #2 Systematically test interactions of rubbed and unrubbed nails.
Behavior of Magnets and Magnetic Materials Record your observations
Behavior of Magnets and Magnetic Materials Based on your observations in Experiments #1 and #2, indicate which of the following statements is supported by the evidence. • A rubbed nail is a ferromagnetic material and behaves like a magnet. • A rubbed nail is a ferromagnetic material but does not behave like a magnet. • An unrubbed nail is a ferromagnetic material and behaves like a magnet. • An unrubbed nail is a ferromagnetic material but does not behave like a magnet.