Energy, Climate, Environment

Classroom Activities

Activity #1

This first activity will be the introductory lesson for the entire unit and is for both 4 ^th and 5 ^th grade students. The objective for this lesson is for students to gain a basic and tangible understanding of what energy is and that energy has different forms. Rather than leading in with a description or definition of what energy is and following it with an activity to demonstrate that property, this activity will have a more open ended activity followed by classroom discussion. The activity is designed around students visiting stations that demonstrate different properties or types of energy. Students will take with them a worksheet that has a repeating question on it. The question is very simple: Based on what you did/saw in station # (1, 2, 3, etc.), what do you think energy is? The strategy behind this activity is for students to construct their own definition of energy drawing from their own body of prior knowledge rather than information dispensed by the teacher. Teacher can advise students that they will likely have a variety of answers for the question, depending on the station. Listed below are ideas for six possible stations, but the options are numerous and only limited by your imagination. Instructions for the station as well as any additional instructions necessary for safety or classroom management concerns should be posted on index cards near the station.

1. The first item in the station is a cup with a balloon stretched tightly over the opening. On the surface of the balloon a small amount of pepper should be sprinkled. Other items at the station should include a tuning fork(s) and a shallow tray of water. Instructions posted at the station should guide students to strike the tuning fork and touch the surface of the water, observing what happens. The second instruction is to strike the tuning fork again and hold it near the ballooned surface of the cup without actually touching it. Student should be able to observe the pepper "jumping" on the balloon surface.
2. This station should contain both an activated chemical hand warmer and an activated chemical ice pack. The instructions should guide students to feel each item and think about where the heat and the cold might be coming from.
3. This station should contain a radiometer and a flashlight. The instructions should guide students to experiment by holding the flashlight at varying distances and observe changes in movement of the radiometer.
4. This station should contain a simple catapult made out of a large paper clip and an unsharpened pencil. Slide pencil through the closed end of the paper clip between the two loops. Lay the paper clip along the body of the pencil and as you push down on the pencil it should form a catapult that can be used to toss small wads of paper quite a good distance. A visual demonstration of how this works can also be viewed online. ¹⁸
5. This station should contain one D-cell battery, one small piece of copper wire, and one 1.5 volt flashlight bulb. The instructions for student should challenge them to see if they can make the bulb light up.
6. This station should include a set of "happy" (Neoprene®) and "sad" (Norsorex®) balls. Students should drop each of the balls and observe what happens. Although the balls appear to be identical, the happy ball will bounce back like expected whereas the sad ball will simply land with a thud and no rebound. These balls can be purchased at many different scientific supply companies, but are available through Arbor Scientific for $ 3.95 per pair. (Product ID P6-1000)

After the class has had an opportunity to visit each station, students should return to their seats for classroom discussion. Have students share what preliminary ideas about or definitions of energy they discovered. A list of ideas can be kept on the blackboard or overhead projector and the teacher should categorize the students responses by energy forms (without labeling them) so that at the end of the lesson students should start to be able to get an intuitive picture of what some of the different forms of energy are.

Activity #2

This activity is for 5 ^th grade students and involves the construction of an overshot waterwheel. The primary objective for this lesson is for students to gain a concrete understanding of how water's energy can be harnessed to do work. A secondary objective is for students to think about the variables in waterwheel construction that can be changed to optimize its performance. This lesson will be done in partner pairs. For each group you will need: two styrofoam plates (or large thick cardboard discs), one 12" piece of small diameter wood dowelling, 9 small bathroom size plastic cups, a small amount of modeling clay, a piece of plastic cord cover (the style that is open on one side), string, ruler, protractor, pencil, scissors, stapler, small items to put in one cup that will serve as the load (marbles, erasers, paperclips, etc.), and a source of water such as a faucet or garden hose.

First, have students locate the center of each plate. Using the protractor have students draw four diameters at 45° angles on one of the plates to locate eight of the plastic cups. Each cup will then be stapled with the opening of the cup parallel to each of the eight lines. (See Figure 4.0) Start a small hole in the center of each plate with the scissors and slide through the dowelling. The cups should now be sandwiched in between both plates with the dowel protruding from either side. Use a small piece of modeling clay to secure the dowel to the outside of each plate. If you have older students or the teacher wants to do this step, you may also affix it with hot glue which will be more permanent, however caution should be used not to use so much glue that it burns all the way through the styrofoam. Next, tie a piece of string in a circle around the lip of the last cup, leaving two free ends to be tied in a triangle above the lip of the cup for balance. This will become a container for lifting the load. The remainder of the string should be tied to the middle of the dowel protruding from one side. Your waterwheel is now ready for action. The piece of plastic cord cover will be used as a "flume" to direct your water to overshoot the water wheel. (See Figure 4.0) If plastic cord cover is unavailable you may also fashion one out of a few layers of aluminum foil bent into a channel like shape.

The water wheel should be held by the students using the other side of the dowel, without the cup attached, as a handle. Direct students to hold it securely, but not so firmly that the dowel won't spin in their hand. Have students test out their water wheels starting with just the empty cup first. As the water flows through the cups on the wheel, the wheel will spin-wrapping the string around the dowel and lifting the cup (load). Students can then experiments with different load weights to see how much their water wheel can handle as well as adjusting the flow of water. Towards the end of the lesson students should be asked to think about how they could design a water wheel (using household items) capable of doing even a greater amount of work. Students should use their laboratory notebooks to draw out their design with a list of materials as well as writing a short description of why they chose their materials and believe them able to create the best water wheel. If you wanted to extend the activity to homework or give extra credit, you could challenge students to construct their new designs at home and bring them into the classroom to test.

Figure 4.0

Activity #3

This activity is for 4 ^th grade students and will be the first activity done when the two groups diverge to explore their separate energy source(s). The focus of this lesson is collecting energy from the sun passively in the form of heat. The primary objective of the lesson is for students to understand that the sun gives us energy in the form of heat and that different materials absorb that heat in varying amounts. A secondary objective is for students to understand that dark materials absorb more of the sun's energy than lighter materials. This activity will be performed in partner pairs. The materials needed for each group include: four plastic cups (clear or white), black paint, a 1-cup measuring cup, water, sand, soil (potting or garden soil), 4 submersible thermometers, laboratory notebooks, and a pencil. The teacher will also need a stopwatch. Prior to beginning the lesson, one cup for each group should have its interior painted with black paint and be allowed to dry.

Students will keep a notebook of this experiment following the steps of the scientific method. It is up to the teacher whether or not he/she wants the students to write out the entire procedure in their notebook and draw out their own chart for recording data or if a worksheet is to be used where students just fill in the information and attach it to their notebook. This decision can be made based upon whether you want students to practice their writing skills or whether you want to shorten the length of time needed to perform the experiment. The important part is that students make their own hypotheses before performing the experiment, collect and record their own data, and make conclusions from their results. In their hypothesis, students should predict which material they think is going to heat up fastest (rank the materials #1-4) as well as which material they think is going to cool down the fastest (rank the materials #1-4).

To begin the experiment have students fill the black painted cup with 1 cup of water, fill cup #2 with one cup of water, fill cup #3 with one cup of sand, and fill cup #4 with one cup of soil. Place one thermometer into each cup. This experiment will last for 40 minutes once started. The cups will be placed for 20 minutes in the sun with temperature readings being taken every 5 minutes and for 20 minutes in the shade with temperature readings being taken every 5 minutes. It is important that students take a 0 minute base reading (once you are outside) of each material because they will not necessarily be the same temperature and classroom thermometers usually vary by several degrees. The teacher will be the time-keeper for the activity and announce when it is time to read the temperature, as well as when that time is approaching so that students can get ready. Partners should take turns either reading or recording. If students have not used thermometers before, a brief lesson beforehand on how to read thermometers would be in order. After all data is collected, students should calculate the temperature change in the sun by subtracting the starting temperature from the ending temperature for each material. Students should then calculate the temperature in the shade by subtracting the ending temperature from the starting temperature. Students should now compare which materials saw the greatest increase in temperature in the sun and decrease in temperature in the shade. Classroom discussion can be opened up on why students believe each material behaved as it did. Teacher should guide discussion, through questioning, in a way that leads to appropriate scientific conclusions without going to the extent of providing "the answers". Students should now write their statements of conclusion in their laboratory notebooks.