In 1986 at the Tulane Conference, the pedagogy of calculus was reviewed, and their first recommendation was to focus on conceptual understanding. To convey ideas, teachers should present topics geometrically, numerically, and algebraically. Recently, this has been expanded to include a verbal description of the topic. Students have preferred learning mechanisms; hopefully by presenting four different perspectives, calculus teachers can cater to the students' tastes.
Many textbooks could benefit from a similar multiple exposition of topics. My accounting textbook really needs to provide an algebraic derivation of accounting's "rules". That which seems arbitrary is actually (and always) quite well founded upon the axioms of accounting, as accounting is completely internally consistent. Unfortunately, the authors leave the algebra as an exercise for the reader.
It's interesting to note that Miles/Gallon fuel efficiency ratings are done by the EPA, and that the maximum speed when testing highway conditions is 60mph. I guess we have to read up on individual cars to determine their most fuel efficient highway speed. I'm searching for some balance between safety, fuel efficiency, and utility, so I think I'm leaning towards a station wagon of some kind(VW Jetta Wagon TDI, or a Volvo 240, Saturn SW/LW, or something else?)