We have a new chemistry teacher this year. At his old school he used these conductivity meters from Flinn Scientific. He said they work really well. He had students use them to make qualitative comparisons of the conductivity of different solutions. The only problem I saw was their price tag. They are $22 ea. This is not horrible, but there really isn’t much to them. So I decided to see if I could make them cheaper.
Turns out it was pretty easy to source the components to place the cost at no more than $1.50 ea. So, for the price of one of Flinn’s meters I can make a classroom set.
I created a set of instructions for making your own: Conductivity Meter Tutorial (PDF)
I used Plasq’s ComicLife to create this. I’d forgotten how much I enjoy using this for making tutorials.