Can the integration of hands-on experimentation combined with visualizations based
on physical data with those created by models support deeper understanding by middle
school students of the difficult concepts of heat and temperature? Can we extend
the student experience and learning from conductivity and thermal gradients in different
materials further to include radiation, convection, and small and large-scale atmospheric
physics?
These are the questions this NSF-funded research project is working to answer.
The Spring 2001 issue of our Newsletter @Concord has two articles on this project describing our work in schools and some of the technology development.
Currently we are developing hardware, software, and curriculum to use with an after-school club of middle school kids in Maynard Massachusetts during the first half of 2001. We plan to start with investigations of thermal conductivity and temperature gradients, progress to understanding the temperature sensing and thermodynamic qualities of the human body, continue with investigations of both radiation and convection and end with investigations into micro and macro atmospheric climate. Read more specific details of our plans in the school for the first half of 2001.
It is our hypothesis that understanding thermodynamics is difficult and that the combination of specially adapted visualizations of both data collected from the environment and physical objects the students manipulate as well as models created and simulated inside a computer will support deeper and more transferable understandings.
In order to best support individual student investigation as well as group collaboration we have decided to build the computer tools for investigation around wireless color handheld computer systems. Specifically the Compaq iPaq H3600 series with the Compaq WL100 wireless ethernet card in a pcmcia jacket. Each student will have a handheld on which data from the physical world or models can be displayed and communicated.
The first suite of hardware and software we have developed is for investigations of thermal conductivity and thermal gradients in different materials. Our system involves small blocks of aluminum, stainless steel and nylon with temperature sensors embedded within the blocks. The blocks can be connected together to form simple or complex two dimensional arrangements. We have also created thermal actuators which can pump heat into or out of the a system. Data are taken from the thermal network and broadcast wirelessly by a java microcontroller to any student with an iPaq interested in visualizing the change in temperature gradients over time. For more information on this system go to the thermal conductivity system page.
Our second effort involves the creation of a tiny ultra-fast response temperature probe for investigations of the surface temperatures of objects in the environment. The sensor will come to thermal equilibrium in less than 5 seconds in still air, have a resolution of better than 0.05 degrees Celsius, and be powered directly from the iPaq's serial port. Each student will have an iPaq with one of these probes attached. Initially these probes will be used to help understand the how the human body senses the temperature of the objects it comes in contact with. For example a student will easily be able to measure the surface temperature of both room temperature metal and plastic objects and determine that the temperatures are identical. Next she can measure the temperature of the skin on her own fingertips. By then touching the metal and plastic objects and measuring the change in temperature over time at the interface between skin and room-temperature object she will start be able to untangle the concepts of temperature, thermals mass, and conductivity.
This ultra-fast response temperature probe will also be used to investigate convection in air. While each iPaq will only have one probe attached to it the wireless capability will be used to enable real-time display and comparison among the temperatures measured by groups of students plotting the extent of cold or hot thermal plumes as they convect away from their sources. For example the temperature gradient in air next to a cold window in winter can be measured visualized simultaneously by a group of students. The probe is sensitive enough to detect the thermal plume rising 10 cm above a students hand in room temperature air.
After this we intend to use the same probe technology reconfigured into a simple thermopile sensor for investigation of radiative heat transfer. A thermopile measures the radiation incident upon its surface. With this probe students will be able to investigate how objects both lose and gain heat energy by radiation and extend these investigations into measurements and understandings about the radiative balance of the earth with questions like the following. Why does the ground gets so much colder on clear nights?
Project Director: Paul Horwitz
Project Staff: Stephen Bannasch, Scott Cytacki, Ed
Hazzard, Carolyn Staudt