Directions 1. (Day 1) Use the instructional model to show students where they are in the course of the unit Show slide 2 of the 3.2 Observing Bread Molding PPT. 2. (Day 1) Remind students of the investigation set up the conducted in the Pre-Lesson. Display slide 3 of the 3.2 Observing Bread Molding PPT. Pass out each student’s copy of the Pre 0.1 Bread Mold Investigation Set Up Worksheet. Use the worksheets and the class results (either in Bread Mold Investigation Class Results 11 x 17 Poster or Spreadsheet form) to review the initial data collected during the Pre-Lesson. Tell students that today they will pick up with the investigation where they left off after the Pre-Lesson. 3. (Day 1) Have students rejoin their Pre-Lesson groups. Display Slide 4 of the 3.2 Observing Bread Molding PPT. Discuss students’ predictions and plans for the investigation that they developed in Activity 3.1 in relation to the investigation tools. It may be helpful to have students look back at their 3.2 Observing Bread Molding Worksheet . Prompt students to connect their predicted observations to their ideas about how matter and energy is moving and changing in the system (e.g., what does it mean for the types of molecules that either enter and leave the mold if you think that the BTB will turn yellow?). At this point, depending on the level of control you gave students in planning the investigation in Activity 3.1, you can either allow students to enact their own investigation (remember it is important that all groups follow the same investigation plan so that comparison across class results is possible) or to follow the investigation plan provided in this activity. 4. (Day 1) Have students read through instructions. Display slide 5 on the 3.2 Observing Bread Molding PPT. Pass out one copy of 3.2 Observing Bread Molding Worksheet to each student. Walk through the steps in Part A and B of the worksheet that overview how to find the combined mass of their Petri dish with bread and mold and where to record the information in Part D, and how to set up the BTB investigation and where to record the information in Part D. 5. (Day 1) Have students record initial data on bread molding. Display slide 6 of the 3.2 Observing Bread Molding PPT. Have students work in their groups of four to complete the Steps in Part A and B on the 3.2 Observing Bread Molding Worksheet , including recording their data in the table in Part D. Slide 6 shows the data table with the sections that students need to fill in at this point indicated with blue outlines. Use Slide 7 to remind students of the range of bromothymol blue (BTB) colors. You may give each group a copy of the BTB Color Handout. 6. (Day 1) Check that students have recorded their data, and wait 24 hours for results. Show slide 8 of the 3.2 Observing Bread Molding PPT. Before leaving the bread and mold with BTB overnight, make sure that the students have recorded the mass of their Petri dishes and color of the BTB on their worksheets. When this is done, leave the bread overnight in sealed containers. 7. (Day 2) Have students record data and observations after 24 hours. Show slide 9 of the 3.2 Observing Bread Molding PPT. Have students collect data record their observations by following the instructions in Part C of their 3.2 Observing Bread Molding Worksheet . Remind students of the range of BTB colors. Alternatively, give each group a copy of the BTB Color Handout to interpret the change in color. 8. Have students organize data using their spreadsheets or poster. Show slide 10 of the 3.2 Observing Bread Molding PPT. Have students input their individual and group results for both mass and color change on the Bread Mold Investigation Class Results 11 x 17 Poster, or in the Bread Mold Class Results Spreadsheet. Spreadsheet instructions: Have individual students report or enter the end mass of each Petri dish into Tab 1 – Individual Data. The spreadsheet will automatically calculate the mass change for each student’s Petri dish in the yellow column. Click to Tab 2 – Group Data and Averages. Have each group enter their beginning and end colors of BTB from their 24 hour investigation. Tab 4 contains sample data in the case that you would like to use that instead. Poster Instructions: Have individual students add up the end mass of the petri dishes and bread for their group and enter this information into the poster. Have each group calculate the total change in mass for their group and record this information on the poster. Have each group enter their beginning and end colors of BTB from their 24 hour investigation. 9. Lead a discussion to help students compare results across groups and identify patterns in the data. Show slide 11 of the 3.2 Observing Bread Molding PPT. Ask students to identify patterns in the data for both the mass change and also the BTB color change, and discuss any outliers or unexplained data points. Note: If you input data into the spreadsheet, the software will construct a graph of the students’ data. You can use the graph to elicit more interpretation of their observations. 10. Watch the end of the Carbon TIME Bread Molding Video. Show slide 12 of the 3.2 Observing Bread Molding PPT. Have students watch the Bread Molding Video starting from where Darryl and Nina show their results to the investigation. Ask the class to compare their own results to Darryl and Nina’s results, pausing the video when the data are shown. 11. Have students compare their class’s data with data from another class. Show slide 13 of the 3.2 Observing Bread Molding PPT. Ask students to compare their results to Ms. Drayton’s class results. Ask students if they recognize similar patterns from their own data. Use the poster or spreadsheet to compare. Ask students if they see the same patterns. What similarities or differences do they notice? What patterns do they see? 12. Have students compare their class’s data for mass results with data from another class. Show slide 14 of the 3.2 Observing Bread Molding PPT. Ask students to compare their mass results to Ms. Drayton’s class results. Ask students if they recognize similar patterns from their own data. Use the poster or spreadsheet to compare. Ask students if they see the same patterns. What similarities or differences do they notice? What patterns can they identify? Support students to recognize the data (e.g., from their class, video, and/or from Ms. Drayton’s class) shows that while the mold grew, the starting mass of the bread was less than the end mass of the bread with the addition of mold. Remind students of the rules about atoms (e.g., this mass must have gone somewhere). Students may have some ideas about where the mass went. Allow them to wonder at this point. Note: The remainder of the unit is based on the assumption that your class results are similar to those of Ms. Drayton’s class and the Bread Molding video. If your class results are significantly different for any reason, after a conversation about why that may have happened, decide whether to have students conduct the investigation again or to refer to Ms. Drayton’s data as they work through the remainder of the unit. 13. Have students complete Part E of their worksheet. Show slide 15 of the 3.2 Observing Bread Molding PPT. Direct students to Part E of their worksheet to describe the patterns they observed during the observation. Help students to recognize that while the mass changes provide them with good evidence to answer the Matter Movement Question, the BTB evidence provides only a partial answer to the Matter Change Question. Tell students that it shows that carbon ends up in CO2 in the air, but not where the carbon came from. 14. Revisit predictions from the previous activity. Display slide 16 of the 3.2 Observing Bread Molding PPT. Ask students to retrieve their completed tools from the previous activity: 3.1 Predictions and Planning Tool for Bread Molding. Have them compare the predictions they made with the results of the investigation. Which predictions were correct? Which predictions were incorrect? What questions do they still need to answer? Remind students that absorbing food is necessary for decomposers to be able to grow, and to be able to use energy for things like moving. Tell students that they will use the data that they collected here to help them to be able to explain two processes that relate to how things decay: decomposers growing and decomposers moving and functioning. 15. Have students complete an exit ticket Show slide 17 of the 3.2 Observing Bread Molding PPT. On a sheet of paper or a sticky note, have students individually answer the exit ticket questions. Depending on time, you may have students answer both questions, assign students to answer a particular question, or let students choose one question to answer. Collect and review the answers. Conclusions: What did you observe during the investigation? Predictions: What do you think is one conclusion you can make from the investigation? The conclusions question will provide you with information about what your students are taking away from the activity. Student answers to the conclusions question can be used on the Driving Questions Board (if you are using one). The predictions question allows students to begin thinking about the next activity and allows you to assess their current ideas as you prepare for the next activity. Student answers to the predictions question can be used as a lead into the next activity.
