There is a diagram of the course. It is at www.texasmotorspeedway.com. Click on
"diagrams and seating chart" then click on "road course map." Although there is
no scale given on the diagram there are data about the length of each course. Of
course your students would be able to use those data to find the radius of
curvature at various points.
This looks like a fun project if one is looking for a change of pace.