Transformations in Matter and Energy Carbon TIME is an NSF-funded partnership led by Michigan State University
Activity 2.5 - Using a Digital Balance and BTB (30 min)
Target Student Performance
Students (a) practice using two key tools for investigation—digital balances and BTB—with accuracy and precision and (b) describe how they can use these tools to detect matter movement and matter change.
Resources You Provide
- BTB, blue (1 cup per group of four students)
- clear plastic cups (1 per group of four students)
- digital balance (1 per group of four students)
- paper clips (10 per group of four students)
- safety glasses (1 per group of four students)
- straws (1 per group of four students)
- 2.5 Class Results for Investigation Tools 11 x 17 Poster
- 2.5 Class Results for Investigation Tools Spreadsheet
- 2.5 Investigation Tools PPT
- Learning Tracking Tool for Systems and Scale (1 per student)
- Assessing the Learning Tracking Tool for Systems and Scale
- (Optional) BTB Color Handout
- BTB Information and Instructions Handout
Prepare the materials listed above for each group, including diluted BTB solution. Use the instructions on the BTB Information and Instructions Handout for details about how to prepare the BTB. Print one copy of the 2.5 Class Results for Investigation Tools 11 x 17 Poster and post it to the wall in an accessible location, or prepare to display the 2.5 Class Results for Investigation Tools Spreadsheet. You may want to print one copy of the BTB Color Handout for each group, but this is optional.
We expect that individual students, and the class as a whole, will often have difficulty identifying sources of error and finding patterns in the data. Yet these skills are essential if they are to interpret the results of their investigations meaningfully. In particular, you will be working with students to identify patterns across multiple replications - for example, when different groups in your class all conduct the same investigation. The students will have to decide what claims about patterns are justified. Listen for their responses to the discussion in the final step to determine if they need more support in identifying sources of error or finding patterns.