Transformations in Matter and Energy Carbon TIME is an NSF-funded partnership led by Michigan State University
Activity 3.2 - Observing Mealworms Eating (60 min over 2 days)
Target Student Performance
Students record data about changes in mass and BTB when mealworms eat, move, and grow 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)
- mealworms (10-15 grams, approximately 100-150 mealworms per group of four students)
- plastic Petri dish (1 per group of four students)
- sealable, 9.5 cup container (1 per group of four students)
- small container to hold mealworms (1 per group of four students)
- thick slice of potato (food for mealworms) (1 per group of four students)
- (From previous lesson) 3.1 Predictions and Planning Tool for Mealworms Eating with student answers
- 3.2 Observing Mealworms Eating Worksheet (1 per student)
- 3.2 Grading the Observing Mealworms Eating Worksheet
- 3.2 Observing Mealworms Eating PPT
- 3.2 Mealworms Investigation Class Results 11 x 17 Poster (1 per class)
- 3.2 Mealworms Investigation Class Results Spreadsheet (1 per class)
- Mealworms Eating Video
- (Optional) BTB Information and Instructions Handout
- BTB Color Handout (1 per group)
Prepare the BTB, mealworms, Petri dishes, potatoes, containers, and safety glasses for students to retrieve for their groups. 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, print the poster before class. Print one copy of 3.2 Observing Mealworms Eating Worksheet for each student. Prepare a computer with an overhead projector to display the 3.2 Observing Mealworms Eating PPT and video. You may want to print one copy of the BTB Color Handout for each group, but this is optional.
Use the class discussion to interpret how successful your students are at identifying patterns in the class data. Use the 3.2 Grading the Observing Mealworms Eating 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 Change 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.
- To save classroom time, the mealworms could be separated from the meal bedding using a colander before the investigation starts.