Author: Dr. Kathie Owens
Participants design an investigation to test various materials to prevent heat gain in frozen water. The posed problem, "Which materials will keep heat away from an ice cube longer than a plastic bag?" is addressed by the participants, who will formulate a hypothesis, conduct an experiment, gather, process and analyze data, and report their findings. Participants will describe transfer of heat by conduction and convection. Participants will discuss helping students develop their investigative skills by using a structured model for problem solving that guides the students without giving them a "recipe" to follow.
Various packing materials (newspaper, foam pellets, fabric, straw, shredded plastic, foil, etc.); ice cubes (be sure these are all the same size and that you have enough for more than one test per group); cups; thermometers*; clock or stopwatch; calculators; graph paper; computer with data display software (optional); temperature-measuring probes (optional)*
*You may conduct the experiment without using devices to measure temperature. Please see the Preparation section for suggestions.
Pose a simple problem to the group - take a sheet of paper and, without leaving your seat, get it into my hands. Notice - this statement poses a problem without asking a question - not every problem is posed in the form of a question. How will you solve this problem? (Most people will fold the paper in such a way as to make a paper airplane, and, if their aim is pretty good, they can easily fly it to your hands without leaving their seats.) Give the participants a couple of minutes to solve this problem.
Explain to the participants that most problems in life are much more complicated and problems tackled by scientists are even more complex than those of daily life are. Problems aren't solved by using a rulebook or a template. That's why, in math, exercises that ask children to apply algorithms in a real world context may not be true problems. But, using an organized structure to assist in solving problems can help make the solving easier. That's what we're going to explore in this session. Encourage discussion about what makes a problem (a dilemma about which the learner knows something about, cannot ascertain the solution immediately or by applying a rule, and has an interest in solving).
Assessment: Before proceeding, by your questions and their responses, make sure that participants understand what makes a situation a problem and can give an example of a problem that would need a non-routine approach to solve.
Pose the problem: "Which materials will keep heat away from an ice cube longer than a plastic bag?" Provide the materials for each group. Discuss safety issues. Ask groups to design their own tests: formulate a hypothesis, conduct an experiment, gather, process and analyze data, and report their findings. Discuss the importance of controlling for all variables, except for the one they are testing (namely, the type of insulation that helps keep the ice cube frozen). See Preparation for some advice on this matter. Ask participants if one trial will be enough to enable reliable conclusions to be made. Remind them that scientists do not conduct only one test. They must look for patterns in their data that hold up over many tests - encourage repeated trials, probably three, which could be done concurrently.
Assessment: Monitor participants' work to check that they are carrying out procedures carefully, taking observations, and recording data accurately. Redirect their attention to the task, as needed. Check to see that each member of the group is participating. Answer participants' questions regarding procedures. Be aware that explanations of the phenomena will be discussed in the next part of the lesson, so do not give answers to questions aimed at explaining "why" something is happening or not happening.
Participants compare their findings with those of other groups and report their findings. Note: it may take an hour or more to effect any changes in the ice cube. Please see Time Frame for some advice on this matter. Ask participants to look for anomalies in their data and to try to explain these differences in relation to the variables within the experiment. Discuss what was learned about heat transfer. See Explanation of the Science for information about heat transfer.
Discuss systematic approaches to problem solving. Point out that too often students in middle grades follow a well-defined recipe when conducting science experiments. On the other hand, students may be frustrated when no guidance is provided. A systematic problem solving approach works well because it provides novices with a structure within which to organize their thinking and proceed to an eventual conclusion.
Note: the description on this site stresses the use of this method in mathematics. The method can be applied within the context of solving a problem in any area. Give an example of a problem from everyday life (like, choosing the color of roofing shingles for a home in Seattle, New Orleans, or Cleveland) whose solving would benefit from using a systematic approach. If time permits, the participants in small groups or as a whole group could address this problem using the six steps of systematic approach to problem solving.
Assessment: Listen to participants' accounts of their findings to judge if their reports are supported to the findings that you observed as experiments were being conducted. Ascertain participants' knowledge of heat transfer by asking questions - see Assessment section for some suggestions. Monitor participants' answers to questions asked in the discussion about problem solving approaches for completeness and accuracy.
Put the participants into groups according to the grade level they teach. Ask them to find an example of an experiment that they use in their science classes that they could rewrite/restructure using the six steps of the systematic problem solving method. Depending on time, participants could either share their work orally with the whole group or submit their written documents to the instructor before the end of the workshop session. A Lesson Implementation Template is provided (below) if you wish to have participants develop a lesson plan for future teaching.
Assessment: Check participants' implementation plans for the presence of the six steps of the systematic problem solving method in their work.
Give participants 2-3 minutes to complete a brief written assessment of the experience. Three short questions will yield much information: 1) What did you learn today? 2) What questions do you still have? 3) How is today's experience relevant to your teaching?
Too often students in middle grades follow a well-defined recipe when conducting science experiments. On the other hand, students may be frustrated when no guidance is provided. Systematic approaches to problem solving work well because they provide novices with a structure within which to organize their thinking and proceed to an eventual conclusion.
Note: the description on this site stresses the use of this method in mathematics. The method can be applied within the context of solving a problem in any area. The investigation in this science activity can be carried out using this systematic approach. Within the bounds of the structure, the learners incorporate their own design, organize data in their own way, and choose their own report of their conclusions.
Content, Technology, and Professional Development:
NSES Content - Physical Science: All students should develop an understanding of transfer of energy.
NSES Content - Science as Inquiry: All students should develop abilities to do scientific inquiry (Content 5-8)
NSES Professional Development - Professional development for teachers of science requires learning essential science content through the perspectives and methods of inquiry. Science learning experiences for teachers must involve participants in actively investigating phenomena that can be studied scientifically, interpreting results, and making sense of findings consistent with currently accepted scientific understanding.
The engagement and exploration should take about one hour. Proceeding to the explanation depends much on the location (warm/cool room) of your event. We recommend that participants make observations over time (for example, every five minutes) and record qualitative data (for example, the cube has formed rounded corners). In pilot testing this module, we planned its use before lunch, then asked participants to observe/record data while they ate. Another way to manage this part of the activity would be to suspend it, move on to another activity, and return to completing this activity in an hour. Intermediate data would not be taken. Results would be ascertained at the end of the time and compared to the beginning.
Many of the insulating materials may be able to be recycled. Proper disposal procedures of other materials should be followed. There are no safety concerns with this lesson, but remind the participants to handle all materials (for example, the thermometers) carefully and to report any breakage to the instructor immediately.
Throughout the lesson, assess participants' learning using questions (informal). Assess their reports using rubrics/suggestions from the lesson for students. See http://pals.sri.com/tasks/5-8/Icemelt/rubric.html
By your actions (asking questions, monitoring the participants' work, giving time for participant-talk) model for participants the assessment techniques they should use in their science classrooms. Ask the participants: In what ways was the PPD (Provider of Professional Development) doing assessment during this lesson? How can science teachers use these ways of assessment in their classrooms?
Ask the participants to share (orally or in writing) an example of a science experiment that their students conduct in their classrooms. Have them tell how the six steps for systematic problem solving can be applied within this experiment.
Heat is the movement of thermal energy from a substance at a higher temperature to another at a lower temperature. Heat can move in three ways: conduction, convection, and radiation. When heat moves directly from one particle to another without the movement of the particles (direct contact), the process is called conduction. Generally, heat moves by conduction in solids. In convection, heat moves as currents within a liquid or a gas. Convection currents form when warm, less dense particles move on top of cooler, denser particles. Radiation is the transfer of heat by electromagnetic waves. Radiation can occur even where there is no matter to transfer thermal energy, such as in outer space.
Adapted from Science Explorer: Motion, Forces, and Energy. (2000). Prentice-Hall
None Available for this Module.
At the website you will find several files whose contents give useful directions to teachers and students, connections to the standards, and a detailed rubric. Examples of students' work are not available. There is no "printer friendly" option for printing the files on the site. You can print each file, however, margins on the paper will not agree with what you see on the screen. We recommend that when using the contents of this site you should use a projection of the material rather than provide hard copies for each participant.
Ask participants to apply the systematic problem solving approach to an everyday problem, like making a budget.
The developers of the PALS activities welcome feedback from users of the site. There is a place on the website where comments may be posted and where the user can read the comments of other users.
In this experience model strategies for meeting the needs of diverse learners. As an example, compose groups with diversity in mind.
None available for this module.