Lifelong learning continues to be popular at UC San Diego Extension, according to a March 19 report from the school.

In 2011, 3,841 students registered for programs at the school, up 19 percent from 2010, said Elizabeth Silva, the registrar and director of student services.

The certificate programs offer practical, concentrated study in a specific professional area, and can usually be earned within one or two years, the school said.

The school offers 102 certificate programs that range in cost from $1,875 to $3,200. Among the programs that showed the highest gains in registration last year were lactation consultant, data mining, copy editing, college counseling, biostatistics, and paralegal studies.

Among the certificate programs added last year were career advising, clinical trials administration in Latin America, global service entrepreneurship, graphic design, in vitro diagnostics, mobile applications development, mobile device programming, and video and imaging technologies.

The programs are generally held online at evenings and weekends at the UCSD campus and two other locations: the Extension University City Center and Extension Mission Valley Center, the university said.