The fastest-growing foreign language class in the past 20 years isn't foreign at all. Nor is it spoken. It's American Sign Language.

More college students are now studying American Sign Language than Chinese and Russian combined. In 2009, ASL was the fourth-most popular language for college students to study, falling behind only Spanish, French, and German.

That's a huge change in the past three decades. So few college students studied sign language in 1986 that it didn't even register on the US Education Department's periodic surveys. By 1990, it was showing up — way, way at the bottom:

Deaf people have their own culture and folkways

After 1990, many more colleges began accepting American Sign Language to fulfill foreign language requirements amid a growing recognition that deaf Americans have their own culture and customs. ASL is now accepted by nearly all flagship state universities for foreign language credits, according to a list maintained by Sherman Wilcox, a University of New Mexico linguistics professor who studies sign languages.

Wilcox, a forceful advocate for the acceptance of American Sign Language as a separate language worthy of study, argues that it has just as much economic value and cultural validity as a foreign language. (ASL isn't widely used outside the United States and Canada, even in other English-speaking countries; the United Kingdom and Australia both have their own sign languages.)

Deaf people have their own culture and folkways, just as French or Spanish speakers do, Wilcox says. Sign language interpreters are in demand in business, education and government. The Bureau of Labor Statistics estimates that the demand for those workers will grow rapidly in the next decade.

the growth of ASL has slowed somewhat in recent years

"One of the educational benefits of foreign language study is that it gives students a fresh perspective on their own language and culture," Wilcox writes. "This is especially true of ASL."

If anything, the growth of ASL has slowed somewhat in recent years. It grew a mere 50 percent between 2002 and 2009; Korean, Arabic, and Chinese all grew faster.

The relative popularity of language classes also offers a window into the changes in US foreign and economic policy and the relative global importance of other nations and economies. Here's how enrollments in Arabic, Chinese, Japanese, and Russian have changed since 1965:



Note the waning of the Cold War (and the fading interest in Russian), the sharp increase in Japanese in the late 1980s, and the spike in Arabic after 2001.