Density, Buoyancy and Convection
In this Earth Science lab, students observe the process of convection and then discover how and why it works through a series of hands-on activities in which they explore and build the various concepts that they need to understand in order to fully construct an understanding of the process of convection. The lab activity culminates in the construction of a concept map to explain how and why convection occurs.
Learn more about the course for which this activity was developed.
Students should learn the concepts of density, buoyancy, thermal expansion and contraction, and convection. Students' skills of observation and construction of conceptual knowledge are developed by this activity.
Context for Use
This activity is appropriate for any educational level from 4th grade on up. It is a hands-on lab activity that can be completed in three hours. All equipment and materials can be readily obtained in hardware and grocery stores. No prerequisite knowledge is required. The activity is situated toward the beginning of my course in Earth and Space sciences but could be used at any time. Since convection is such a powerful concept in the Earth and Space sciences, this lab activity can be built on and referred back to over and over again.
Description and Teaching Materials
Teaching Notes and Tips
This lab takes about three hours to complete. The "Lab Choreography" link below provides a detailed description of how we present and facilitate the lab.
Each lab table is assigned to present their answers to the questions about one of the activities to the rest of the class, using overhead transparencies for illustration. A whole-class discussion follows each presentation.
Students are asked to figure out how a Galilean thermometer and a lava lamp work, using concepts learned in this activity.
Students construct concept maps of the convection process.
References and Resources
Here are some convection-related online resources that you might find useful:
A lesson on upwelling ocean currents for grades 6-8 (www.teachingboxes.org)