I think the best way to start would be to focus on the objective in its simplest form:
We are creating an experiment to teach students about one dimensional conductive heat transfer. Let us take a moment to examine the implications of that statement.
- Teach means educate. Always keep in mind this is the final objective. We are teaching.
- One Dimensional implies linearity. Just about any sample of material will be just fine. However we would be as simple as a wire.
- Conductive refers to heat transfer in a solid medium. Convection and Radiation should take a back seat to this; the experiment should reduce both of those to be negligible.
- Heat Transfer means a examining a change in temperature. We need to figure out what is going to cause that change.
You can get a laser thermometer for about $50. It can take the temperature of an object with touching it. The downside it that is might be difficult to obtain a direct link to a computer for LabView, and it requires the points of the sample that need to be tested to be open to the atmosphere. The advantage is safety and rapid use. Also, lasers are cool.
The creation of a temperature gradient is necessary for this experiment to work. Off the top of my head, we can heat the metal via chemical means (some sort of fueled based flame) or possibly an electric means.
Another part of the temperature gradient could be cooling the other end. Best way to maintain a cold constant temperature would be a fluid kept cold by some sort of refrigerator cycled through a pump or from a reservoir.