In the past three decades, U.S. students have begun blurring the lines between traditional academic studies and technical-education courses, says a new report by researchers at RTI International and MPR Associates Inc.

The researchers found that career and technical education, including in areas such as accounting, construction, and health care, has moved from being a separate vocational "track" for graduates headed to jobs immediately after high school to an exploratory "field" for both academic and general high school graduates.

The researchers also found that students who take several career and technical-education courses have better academic outcomes and college participation than similar students in decades past.

"Historically, career and technical-education courses provided low-achieving students with courses that prepared them for immediate entry into the labor market," says Benjamin Dalton, a statistical analyst at RTI and the report's lead author. "However, the expansion of new types of career education within magnet schools, career academies, and traditional high schools suggests that the older distinction between college-bound academic education and work-oriented occupational preparation are less relevant to today's students."

The study, funded by the U.S. Department of Education, compares the academic course taking and achievement outcomes from the graduating classes of 1982, 1992, and 2004.

"We found that this shift from 'track to field' involves smaller groups of graduates intensively studying an occupational area and larger groups of graduates earning a few occupational credits," Dalton says.

The percent of graduates earning one to two credits in occupational courses grew from 36 percent in 1982 to 42 percent in 2004. However, the percent of graduates earning three or more credits in one occupational area declined from 30 percent to 17 percent from 1982 to 2004.

Other key findings included the following:

•Public high school graduates earned about 4.5 more credits in academic subjects in 2004 than in 1982.

•Total credits earned in career- and technical-education courses and occupation-specific courses declined between 1982 and 1992, but there were no differences between 1992 and 2004.

•In general, graduates who took three or more career and technical-education classes were more likely than students who took fewer career and technical education classes to come from families in the bottom quartile of the socioeconomic status.