Directions 1. Use the instructional model to show students where they are in the course of the unit. Show slide 2 of the 3.1 Predictions and Planning about Mealworms Eating PPT. 2. Introduce Lesson 3 by watching the first half of the Mealworms Video.. Tell students that in this lesson, they will be investigating what happens when mealworms eat, move, and breathe to learn more about what happens to matter and energy during chemical changes. Show slide 3 of the PPT. Watch the Mealworms Eating Video until the first intermission where Darryl and Nina ask students to make predictions about what happens when mealworms eat. Pause the video to discuss the questions posed on the screen before students complete the predictions tool. 3. Review the Matter Movement Question. Display slide 4 of the PPT. Put a copy of the Three Questions 11x17 Poster on the wall for reference if it is not there already. Give each student one copy of the Three Questions Handout or have them take out their existing copies. Draw students’ attention to the poster and point out that each question is accompanied with “rules to follow” as well as ways to “connect atoms to evidence.” Have students highlight, underline, or box the following rule about matter: Atoms are bonded together in molecules. 4. Review the Matter Change Question. Display slide 5 of the PPT. Have students highlight, underline, or box the following rule about matter: Atoms last forever. 5. Review the Energy Change Question. Display slide 6 of the PPT. Have students highlight, underline, or box the following rules about energy: Energy lasts forever, and energy can be transformed. 6. Have students complete Part A of the Predictions and Planning Tool for Mealworms Eating. Show slide 7 of the PPT. Pass out one copy of 3.1 Predictions and Planning Tool for Mealworms Eating to each student, and ask them to record their ideas as individuals for each of the Three Questions for mealworms eating. Remind students that these are just predictions, and that there are no wrong answers at this point. Encourage them to write down all of their ideas on the tool. 7. Discuss the Matter Movement Question as it relates to a digital balance Show slides 8 and 9 of the 3.1 Predictions and Planning about Mealworms Eating PPT. Discuss with students how a digital balance can be used to measure matter moving into or out of a system. Highlight that the mass of the system can be measured before and after a change happens in a system. Discuss the two possible conclusions students can draw from their observations: If the mass of the system increases, then matter must have moved into the system (remember the facts about atoms) If the mass of the system decreases, then matter must have moved out of the system. 8. Discuss Matter Change Question as it relates to BTB Show slide 10 of the 3.1 Predictions and Planning about Mealworms Eating PPT. Discuss with students how BTB can be used to measure matter change in a system. Highlight that the BTB in a closed container can be observed before and after a change happens in the system. Discuss the two possible conclusions students can draw from their observations: If the BTB changes from blue to yellow, then a chemical change may be producing CO2 If the BTB changes from yellow to blue, then a chemical change may be using CO2 as a reactant. 9. Have students complete their predictions for Mealworms Eating: Part B of the Predictions and Planning Tool. Show slide 11 of the PPT. Have students find Part B on 3.1 Predictions and Planning about Mealworms Eating PPT and ask them to record their ideas as individuals for both the matter movement and matter change questions. Remind students that these are just predictions, and that there are no wrong answers at this point. Encourage them to write down all their ideas on the tool. 10. Have students discuss their predictions in pairs. When students have completed Part B of their Predictions and Planning Tools, show slide 12 of the PPT. Divide students into pairs and tell them to compare and contrast their predictions with each other and to look for differences and similarities. Give students 2-3 minutes to compare their predictions. As students are sharing, circulate through the groups. Consider engaging students by: Revoice what students said/wrote (for instance, I see/hear that you think the BTB will turn blue). Why do you think that? What do you two disagree about? Why do you disagree? Pay attention to patterns in students’ predictions as well as predictions that diverge from any of the patterns. Both will be valuable to discuss next as a whole class. 11. Save the Predictions and Planning Tools for later. Display slide 13. Tell students that they will revisit their ideas after the investigation to see how their ideas changed over time. 12. Have students plan the investigation: Part C of the Predictions and Planning Tool Show students Slide 14 of the PPT and describe the instruments and materials necessary for carrying out the investigation. Have students begin planning their investigation. There are two main variations in how much control students can have over this planning process Minimal student control: Discuss student ideas for how an investigation could be set up. Then have students follow the lab instructions for lesson 3.2. Maximal student control: Students in class develop their own consensus plans that will replace the lab instructions in lesson 3.2. (They may use the Investigation Planning Tool for making their plans. Note the importance of having different student groups following the same plan so that they can come to a consensus about patterns in data in lesson 3.2 Some possible ideas of using lab materials are below: Students might choose to add controls to the experiment, for example including both a Petri dish of yellow bromothymol blue (BTB) (made from blowing into the blue BTB with a straw) and a Petri dish of blue BTB to the chamber.
