Materials
Gather these before class.
- Small leafy plants or celery stalks with leaves
- Clear plastic cups
- Food coloring (blue or red)
- Water
- Paper towels
- Magnifying glasses
- Lab observation sheets
- Scissors
Ready-to-use classroom activity
Students conduct a simple, guided investigation to observe and document a process or phenomenon firsthand.
Grade range
Works across
Activity style
Classroom walkthrough
One concrete example you can borrow, adapt, or teach as written.
Example lesson context
Gather these before class.
What to have ready before students begin.
Set up investigation stations with materials. Prepare observation sheets with prediction, observation, and conclusion sections.
A classroom-ready sequence from launch to follow-up.
Introduce the concept of transpiration - how plants move water from roots to leaves.
Demonstration: Show a plant and ask students to predict how water travels through it.
Procedure:
Fill cups with water and add food coloring
Trim plant stems under water to prevent air bubbles
Place stems in colored water
Make an initial observation and drawing
Make predictions about what will happen over time
Observe at intervals (30 minutes, 2 hours, next day)
For final observation: carefully cut open a stem to observe the colored vessels inside
Record all observations with detailed drawings
Class discussion: Compare results and draw conclusions about how water moves through plants
Connect to the larger water cycle and plant systems
Adjust the activity without losing its core purpose.
Younger students focus on simple observations and drawings. Older students measure water levels, calculate transpiration rates, or design variations of the experiment.
Use these signals to assess understanding.
Review observation sheets for accurate recording of data and reasonable conclusions. Listen for use of scientific vocabulary during discussions.