Author: Sandy Van Natta
Source: The original source is unknown
Students will learn to distinguish observations from inferences. Students observe what they think is a burning candle and list all their observations. In reality they are observing a cylinder of apple or potato with a burning nut on the end. When all the students' observations are listed, a discussion is lead to separate actual observations from inferences students have made. Next students observe the appearance and behavior of two balls which are similar in appearance but very different in composition. Observations and inferences are made relating to the two balls.
What should students know as a result of this lesson?
What should the students be able to do as a result of this lesson?
Elaboration Activity- Per Group
Assessment: The evaluation is informal in this stage. Listen to student observations and comments and try to encourage the quieter members of the class to contribute to the list of observations being compiled.
Once you have eaten the "candle" divide the class into groups of 2 and ask each group to evaluate the class list based on the last "event" – eating the candle.
Assessment Monitor the groups' discussions. Ask them to decide if all statements listed were truly observations. Ask them if they made any assumptions not actually based upon their direct observations.
Lead a class discussion on the differences between observations and inferences. Observations are made using the 5 senses. Although sight is the most utilized sense, touch, hearing, and smell are still important. Taste should not be used in the science laboratory. Tools can be used to extend the senses so that quantitative (measurements) observations can be made. (Note – all observations made in this activity are in the form of descriptions and are qualitative in nature.)
Make sure to discuss with students the role technology has played in the development of tools. For example, we have gone from the use of the naked eye, to magnifying glasses, to light microscopes, to electron microscopes for use in viewing small objects. Each advancement in technology allows us to make more detailed observations.
Assessment: Have students look at the list generated by the class on the board. Ask the students divide the statements into two groups – ones that are true observations and ones that are inferences. For example, actual observations would include statements such as the wick was black, it was burning, the flame was orange, etc. Inferences might include such statements as it's a candle, the candle was melting, and the candle was made of wax.
Ask students to write definitions in their own words for an observation and an inference and give an example of each.
Give the students a set of Happy/Sad Balls. Ask them to make a list of observations based on both the appearance of the balls and the behavior of the balls when bounced. Students should be given a meter stick to measure the height of the bounce of each ball and a balance can be used to mass the balls. After completing their list of observations, ask students to make inferences concerning the balls based upon their observations. Observations may include the color, size, mass, and texture of the balls. Inferences may relate to the composition or the density of the balls or whether the balls are solid or hollow.
Assessment: Have students complete the worksheet attached and evaluate the worksheet.
Common Core Standards:
Observations are made using the senses. Descriptions are qualitative in nature. Tools are used to extend the senses. Information obtained using tools is often numerical in form and is therefore quantitative in nature. As technology has given us better and better tools, the number of observations upon which we can base our inferences has greatly increased. For example, we have progressed from looking at the stars with the naked eye, to using ground based telescopes, to space based telescopes. We use computers to store and sort the millions of observations that can be made daily. However, computers do not make the inferences – humans do!
Sometimes students make value judgments and think they are observations. A statement such as the ball is pretty is a judgment and not directly observed or measured.
The Happy and Sad balls used in this activity are made from the polymers (long chains of repeating units) neoprene and polynorbornene, respectively. Neoprene is elastic and used in products such as diving wet suits. Polynorbornene is a good shock absorber and used in tires or even as a lining in ballistic containers used by bomb squads.
No special safety precautions are needed
Students should learn not to make assumptions without the facts.
Observations are vital in forming accurate conclusions in scientific experimentation.
Give students a single frame of a picture from a comic strip. Ask them to list all the observations they can make from looking at the picture. Next ask students to make inferences from their list of observations.
Grouping Suggestions: Be aware of students' abilities and ethnic backgrounds when choosing groups. Try to place students of varied abilities and backgrounds in each group.
Pacing/Suggested Time: The Engagement activity should take about 20 minutes to complete. The Exploration may take up to 30 minutes to complete.