Transformations in Matter and Energy Carbon TIME is an NSF-funded partnership led by Michigan State University
Activity 3.2: Observing Bread Molding (60 min over 2 days)
Target Student Performance
Students record data about changes in mass and BTB when bread molds and reach consensus about patterns in their data.
Resources You Provide
- bromothymol blue (BTB) solution (less than 1 cup per group of four students)
- digital balance (1 per group of four students)
- plastic Petri dish (1 per group of four students)
- labeled Petri dishes with moldy bread from the Pre-Lesson (1 per student)
- (From previous lesson) Completed Pre 0.1 Bread Mold Investigation Set Up Worksheet
- (From previous lesson) Bread Mold Investigation Class Results 11 x 17 Poster (or Spreadsheet)
- 3.2 Observing Bread Molding Worksheet (1 per student)
- 3.2 Grading the Observing Bread Molding Worksheet
- 3.2 Observing Bread Molding PPT
Prepare the BTB, digital balances, Petri dishes, containers, and the materials from the Pre-Lesson. Use the instructions on the BTB Information and Instructions Handout for details about how to prepare the BTB. If you plan to use the poster to record student data, re-post the poster on the wall. Print one copy of 3.2 Observing Bread Molding Worksheet for each student. Prepare a computer with an overhead projector to display the PPT and video. You may want to print one copy of BTB Color Handout for each group, but this is optional.
- Use the class discussion when you compare their data to Mrs. Drayton’s class to interpret how successful your students are at identifying patterns in the class data. Use the 3.2 Grading the Observing Bread Molding Worksheet to determine if your students had any trouble with data collection.
- During this activity, note students' success in measuring changes in mass and BTB. Also note students' ability to reach a consensus about patterns in data and how they interpret results.
- The discussions in steps 10 and 12 can be helpful for informal assessment in two ways: 1) It can help you assess your students’ skills in identifying sources of error and finding patterns in data, and 2) it can help you assess how well students identify the limits of the evidence. Do they recognize that the investigation does not fully answer the Matter Change Question or the Energy Question?
- Be sure to collect results from the different groups and compare their measurements.
- Discuss threats to accuracy of measurement.
- Check to see if students can identify unanswered questions from the investigation.