Advisors are always looking for different ways to help students understand land judging and soil science and well sometimes to have to get the clipboards out and hit the dirt to find the solution. However, Roseburg FFA took a neat approach to using their clipboards. Gather topsoil samples from various sites and put them next to each other on the clipboard to evaluate.
By simply looking, feeling, and breaking the clods students discover the differences in soil types. When that happens then they discover why soil science is so important. If you can't get the class in the field, then fill a few zip-lock bags with different soil types and try it in the classroom, shop, or parking lot for that matter.
If you need some help explaining the importance of porosity, permeability, and percolation then take a look at this post about the desktop well. You can bring "how wells get their water" to the classroom.
If you want to learn some more about Land Judging, then here's a link to the Nebraska NRCS where they have a lot of information that can help you out.
Believe it or not we have Soil Science Lesson Plans that introduce students into the importance of land evaluation and soil formation. You can also send me a question students frequently ask about Land Judging at firstname.lastname@example.org