Activity 3.2GL: Observing Plants’ Mass Changes, Part 1 (30 min)

Target Student Performance

Students harvest their radish plants and dry down the plants and the paper towel or gel in preparation for Activity 3.4.

Resources You Provide

  • Tubes of radish plants from the Pre-Lesson (1 per student)
  • Digital scale (1 per group)
  • Small containers to collect gel from individual tubes to mass.
  • Small paper bags or envelopes for drying plants (1 per plant)
  • Sunny windowsill or drying oven (domestic ovens work at low settings)
  • Markers to label plants by student or group (1 per group)

Resources Provided


  • Each student or group of 4 students should have 1-2 tubes. For each group, provide a container to collect the gel that the students will extract from the plant roots. Unless you choose to dry out the gel, it will be discarded after the investigation.
  • Provide a paper towel, small paper bags, or envelopes (1 per plant), on which to place the plants to dry.
  • After the activity, students can assist with cleanup by rinsing out the plant test tubes.
  • Prepare your computer and projector for the 3.2GL Observing Plants’ Mass Changes, Part 1 PPT.
  • Print one copy per student of the 3.2GL Observing Plants’ Mass Changes, Part 1 Worksheet.


1. Use the instructional model to show students where they are in the course of the unit.

  • Strategic grouping with strong speakers 
  • Compare class data orally and on the spreadsheet
Extending the Learning
  • Follow the same procedures to investigate other plants growing, such as peas