Author: Sandy Van Natta
Source: The original source is unknown
- Discuss the importance of making observations in science.
- Tell your students you are going to do an activity in front of the class and ask students to make as many observations as they can. (Avoid using the word candle.)
- Ask for a student volunteer to record the students' observations for all to see the list.
- Light the "candle" without comment and have the volunteer begin listing the observations.
- Before the flame has a chance to burn out on its own, blow out the candle, allow a few seconds for the wick to cool, and eat the candle.
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.