A couple things, actually.Well any input?
1) what is this dual ranged force sensor that you have, and how does it work? also, what units are you working in? (just curious)
2) I agree with haruspex, how are you maintaining consistency while doing these experiments? It seems as though you're cooling, then moving to room temperature, then conducting your run to gather data. How do you think the results would compare if you were to do your "frigid" experiment in an environment where the ambient temperature is "frigid"?
The purpose of this project is to see what kind of material has a higher coefficient of friction, and therefore better grip, no? If you are wearing a shoe out and about, the shoe is going to be at about the temperature of what the air is around it (assuming you've been, say, outside long enough, or wherever you need to be to get the variable conditions you're testing).
Otherwise, it seems like you're doing alright, especially for an 8th grade science fair project. If you would, respond and we can take it from there.
Sorry for delay, I tend to post while at work, and if we get busy, I just don't have time to respond.