Federal Highway Administration
The Federal Highway Administration is a division of the Department of Transportation. The administration's overall goal, according to their website, is to "improve mobility on our nation's highways." Priorities include reduction of traffic congestion, environmental awareness, and roadway safety.
The primary feature of FHWA web resources available to educators is a wide variety of statistical data. Using the information offered will require preparation, as lessons or activities will need to be built around the offered information. Possibilities include asking your students to look at older and recent statistics and make suggestions for the differences between the two data sets. How has U.S. daily life and technology changed in ways which support altered transportation trends?
Two sources which would be optimal for the above suggested activity include Traffic Volume Trends, which date from 1970 through 2009, and the National Household Travel Survey. The latter includes vehicle occupancy, public transportation availability, household travel, mode of transportation, characteristics of drivers with licenses, and more. The years covered are 1969, 1977, 1983, 1990, 1995, and 2001.
Other options exist to find articles and data which fit your classroom's needs. These include the National Transportation Library, the FHWA's Publications and Products page, and the Bureau of Transportation Statistics.